diff --git a/.github/workflows/golangci-lint.yml b/.github/workflows/golangci-lint.yml
new file mode 100644
index 0000000..f67bbe6
--- /dev/null
+++ b/.github/workflows/golangci-lint.yml
@@ -0,0 +1,23 @@
+name: golangci-lint
+on: [ push, pull_request ]
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v2
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          # Required: the version of golangci-lint is required and must be specified without patch version: we always use the latest patch version.
+          version: v1.29
+
+          # Optional: working directory, useful for monorepos
+          # working-directory: somedir
+
+          # Optional: golangci-lint command line arguments.
+          args: --timeout=10m
+
+          # Optional: show only new issues if it's a pull request. The default value is `false`.
+          # only-new-issues: true
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7d25f2a..d3766eb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+1.8.0
+  - add "chain time"
+  - add "validator keycheck"
+
 1.7.5:
   - add "slot time"
   - add "attester duties"
diff --git a/cmd/chain/time/input.go b/cmd/chain/time/input.go
new file mode 100644
index 0000000..5206d3c
--- /dev/null
+++ b/cmd/chain/time/input.go
@@ -0,0 +1,81 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+import (
+	"context"
+	"time"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/viper"
+)
+
+type dataIn struct {
+	// System.
+	timeout time.Duration
+	quiet   bool
+	verbose bool
+	debug   bool
+	json    bool
+	// Input
+	connection               string
+	allowInsecureConnections bool
+	timestamp                string
+	slot                     string
+	epoch                    string
+}
+
+func input(ctx context.Context) (*dataIn, error) {
+	data := &dataIn{}
+
+	if viper.GetDuration("timeout") == 0 {
+		return nil, errors.New("timeout is required")
+	}
+	data.timeout = viper.GetDuration("timeout")
+	data.quiet = viper.GetBool("quiet")
+	data.verbose = viper.GetBool("verbose")
+	data.debug = viper.GetBool("debug")
+	data.json = viper.GetBool("json")
+
+	haveInput := false
+	if viper.GetString("timestamp") != "" {
+		data.timestamp = viper.GetString("timestamp")
+		haveInput = true
+	}
+	if viper.GetString("slot") != "" {
+		if haveInput {
+			return nil, errors.New("only one of timestamp, slot and epoch allowed")
+		}
+		data.slot = viper.GetString("slot")
+		haveInput = true
+	}
+	if viper.GetString("epoch") != "" {
+		if haveInput {
+			return nil, errors.New("only one of timestamp, slot and epoch allowed")
+		}
+		data.epoch = viper.GetString("epoch")
+		haveInput = true
+	}
+	if !haveInput {
+		return nil, errors.New("one of timestamp, slot or epoch required")
+	}
+
+	if viper.GetString("connection") == "" {
+		return nil, errors.New("connection is required")
+	}
+	data.connection = viper.GetString("connection")
+	data.allowInsecureConnections = viper.GetBool("allow-insecure-connections")
+
+	return data, nil
+}
diff --git a/cmd/chain/time/input_internal_test.go b/cmd/chain/time/input_internal_test.go
new file mode 100644
index 0000000..f409a3b
--- /dev/null
+++ b/cmd/chain/time/input_internal_test.go
@@ -0,0 +1,97 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/require"
+	"github.com/wealdtech/ethdo/testutil"
+	e2types "github.com/wealdtech/go-eth2-types/v2"
+	e2wallet "github.com/wealdtech/go-eth2-wallet"
+	keystorev4 "github.com/wealdtech/go-eth2-wallet-encryptor-keystorev4"
+	nd "github.com/wealdtech/go-eth2-wallet-nd/v2"
+	scratch "github.com/wealdtech/go-eth2-wallet-store-scratch"
+	e2wtypes "github.com/wealdtech/go-eth2-wallet-types/v2"
+)
+
+func TestInput(t *testing.T) {
+	if os.Getenv("ETHDO_TEST_CONNECTION") == "" {
+		t.Skip("ETHDO_TEST_CONNECTION not configured; cannot run tests")
+	}
+
+	require.NoError(t, e2types.InitBLS())
+
+	store := scratch.New()
+	require.NoError(t, e2wallet.UseStore(store))
+	testWallet, err := nd.CreateWallet(context.Background(), "Test wallet", store, keystorev4.New())
+	require.NoError(t, err)
+	require.NoError(t, testWallet.(e2wtypes.WalletLocker).Unlock(context.Background(), nil))
+	viper.Set("passphrase", "pass")
+	_, err = testWallet.(e2wtypes.WalletAccountImporter).ImportAccount(context.Background(),
+		"Interop 0",
+		testutil.HexToBytes("0x25295f0d1d592a90b333e26e85149708208e9f8e8bc18f6c77bd62f8ad7a6866"),
+		[]byte("pass"),
+	)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name string
+		vars map[string]interface{}
+		res  *dataIn
+		err  string
+	}{
+		{
+			name: "TimeoutMissing",
+			vars: map[string]interface{}{},
+			err:  "timeout is required",
+		},
+		{
+			name: "ConnectionMissing",
+			vars: map[string]interface{}{
+				"timeout": "5s",
+				"slot":    "1",
+			},
+			err: "connection is required",
+		},
+		{
+			name: "IDMissing",
+			vars: map[string]interface{}{
+				"timeout":    "5s",
+				"connection": os.Getenv("ETHDO_TEST_CONNECTION"),
+			},
+			err: "one of timestamp, slot or epoch required",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			viper.Reset()
+
+			for k, v := range test.vars {
+				viper.Set(k, v)
+			}
+			res, err := input(context.Background())
+			if test.err != "" {
+				require.EqualError(t, err, test.err)
+			} else {
+				require.NoError(t, err)
+				require.Equal(t, test.res.timeout, res.timeout)
+			}
+		})
+	}
+}
diff --git a/cmd/chain/time/output.go b/cmd/chain/time/output.go
new file mode 100644
index 0000000..a24b6ec
--- /dev/null
+++ b/cmd/chain/time/output.go
@@ -0,0 +1,67 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"time"
+
+	spec "github.com/attestantio/go-eth2-client/spec/phase0"
+	"github.com/pkg/errors"
+)
+
+type dataOut struct {
+	debug   bool
+	quiet   bool
+	verbose bool
+	json    bool
+
+	epoch      spec.Epoch
+	epochStart time.Time
+	epochEnd   time.Time
+	slot       spec.Slot
+	slotStart  time.Time
+	slotEnd    time.Time
+}
+
+func output(ctx context.Context, data *dataOut) (string, error) {
+	if data == nil {
+		return "", errors.New("no data")
+	}
+
+	if data.quiet {
+		return "", nil
+	}
+
+	builder := strings.Builder{}
+
+	builder.WriteString("Epoch ")
+	builder.WriteString(fmt.Sprintf("%d", data.epoch))
+	builder.WriteString("\n  Epoch start ")
+	builder.WriteString(fmt.Sprintf("%s", data.epochStart.Format("2006-01-02 15:04:05")))
+	builder.WriteString("\n  Epoch end ")
+	builder.WriteString(fmt.Sprintf("%s", data.epochEnd.Format("2006-01-02 15:04:05")))
+
+	builder.WriteString("\nSlot ")
+	builder.WriteString(fmt.Sprintf("%d", data.slot))
+	builder.WriteString("\n  Slot start ")
+	builder.WriteString(fmt.Sprintf("%s", data.slotStart.Format("2006-01-02 15:04:05")))
+	builder.WriteString("\n  Slot end ")
+	builder.WriteString(fmt.Sprintf("%s", data.slotEnd.Format("2006-01-02 15:04:05")))
+	builder.WriteString("\n")
+
+	return builder.String(), nil
+}
diff --git a/cmd/chain/time/output_internal_test.go b/cmd/chain/time/output_internal_test.go
new file mode 100644
index 0000000..44ba638
--- /dev/null
+++ b/cmd/chain/time/output_internal_test.go
@@ -0,0 +1,85 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+// import (
+// 	"context"
+// 	"testing"
+//
+// 	api "github.com/attestantio/go-eth2-client/api/v1"
+// 	"github.com/stretchr/testify/require"
+// 	"github.com/wealdtech/ethdo/testutil"
+// )
+//
+// func TestOutput(t *testing.T) {
+// 	tests := []struct {
+// 		name    string
+// 		dataOut *dataOut
+// 		res     string
+// 		err     string
+// 	}{
+// 		{
+// 			name: "Nil",
+// 			err:  "no data",
+// 		},
+// 		{
+// 			name:    "Empty",
+// 			dataOut: &dataOut{},
+// 			res:     "No duties found",
+// 		},
+// 		{
+// 			name: "Present",
+// 			dataOut: &dataOut{
+// 				duty: &api.AttesterDuty{
+// 					PubKey:                  testutil.HexToPubKey("0x933ad9491b62059dd065b560d256d8957a8c402cc6e8d8ee7290ae11e8f7329267a8811c397529dac52ae1342ba58c95"),
+// 					Slot:                    1,
+// 					ValidatorIndex:          2,
+// 					CommitteeIndex:          3,
+// 					CommitteeLength:         4,
+// 					CommitteesAtSlot:        5,
+// 					ValidatorCommitteeIndex: 6,
+// 				},
+// 			},
+// 			res: "Validator attesting in slot 1 committee 3",
+// 		},
+// 		{
+// 			name: "JSON",
+// 			dataOut: &dataOut{
+// 				json: true,
+// 				duty: &api.AttesterDuty{
+// 					PubKey:                  testutil.HexToPubKey("0x933ad9491b62059dd065b560d256d8957a8c402cc6e8d8ee7290ae11e8f7329267a8811c397529dac52ae1342ba58c95"),
+// 					Slot:                    1,
+// 					ValidatorIndex:          2,
+// 					CommitteeIndex:          3,
+// 					CommitteeLength:         4,
+// 					CommitteesAtSlot:        5,
+// 					ValidatorCommitteeIndex: 6,
+// 				},
+// 			},
+// 			res: `{"pubkey":"0x933ad9491b62059dd065b560d256d8957a8c402cc6e8d8ee7290ae11e8f7329267a8811c397529dac52ae1342ba58c95","slot":"1","validator_index":"2","committee_index":"3","committee_length":"4","committees_at_slot":"5","validator_committee_index":"6"}`,
+// 		},
+// 	}
+//
+// 	for _, test := range tests {
+// 		t.Run(test.name, func(t *testing.T) {
+// 			res, err := output(context.Background(), test.dataOut)
+// 			if test.err != "" {
+// 				require.EqualError(t, err, test.err)
+// 			} else {
+// 				require.NoError(t, err)
+// 				require.Equal(t, test.res, res)
+// 			}
+// 		})
+// 	}
+// }
diff --git a/cmd/chain/time/process.go b/cmd/chain/time/process.go
new file mode 100644
index 0000000..1cdc992
--- /dev/null
+++ b/cmd/chain/time/process.go
@@ -0,0 +1,90 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+import (
+	"context"
+	"strconv"
+	"time"
+
+	eth2client "github.com/attestantio/go-eth2-client"
+	spec "github.com/attestantio/go-eth2-client/spec/phase0"
+	"github.com/pkg/errors"
+	"github.com/wealdtech/ethdo/util"
+)
+
+func process(ctx context.Context, data *dataIn) (*dataOut, error) {
+	if data == nil {
+		return nil, errors.New("no data")
+	}
+
+	eth2Client, err := util.ConnectToBeaconNode(ctx, data.connection, data.timeout, data.allowInsecureConnections)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to connect to Ethereum 2 beacon node")
+	}
+
+	config, err := eth2Client.(eth2client.SpecProvider).Spec(ctx)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to obtain beacon chain configuration")
+	}
+
+	slotsPerEpoch := config["SLOTS_PER_EPOCH"].(uint64)
+	slotDuration := config["SECONDS_PER_SLOT"].(time.Duration)
+	genesis, err := eth2Client.(eth2client.GenesisProvider).Genesis(ctx)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to obtain genesis data")
+	}
+	//epoch = int64(time.Since(genesis.GenesisTime).Seconds()) / (int64(slotDuration.Seconds()) * int64(data.slotsPerEpoch))
+
+	results := &dataOut{
+		debug:   data.debug,
+		quiet:   data.quiet,
+		verbose: data.verbose,
+	}
+
+	// Calculate the slot given the input.
+	switch {
+	case data.slot != "":
+		slot, err := strconv.ParseUint(data.slot, 10, 64)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to parse slot")
+		}
+		results.slot = spec.Slot(slot)
+	case data.epoch != "":
+		epoch, err := strconv.ParseUint(data.epoch, 10, 64)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to parse epoch")
+		}
+		results.slot = spec.Slot(epoch * slotsPerEpoch)
+	case data.timestamp != "":
+		timestamp, err := time.Parse("2006-01-02T15:04:05", data.timestamp)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to parse timestamp")
+		}
+		secs := timestamp.Sub(genesis.GenesisTime)
+		if secs < 0 {
+			return nil, errors.New("timestamp prior to genesis")
+		}
+		results.slot = spec.Slot(secs / slotDuration)
+	}
+
+	// Fill in the info given the slot.
+	results.slotStart = genesis.GenesisTime.Add(time.Duration(results.slot) * slotDuration)
+	results.slotEnd = genesis.GenesisTime.Add(time.Duration(results.slot+1) * slotDuration)
+	results.epoch = spec.Epoch(uint64(results.slot) / slotsPerEpoch)
+	results.epochStart = genesis.GenesisTime.Add(time.Duration(uint64(results.epoch)*slotsPerEpoch) * slotDuration)
+	results.epochEnd = genesis.GenesisTime.Add(time.Duration(uint64(results.epoch+1)*slotsPerEpoch) * slotDuration)
+
+	return results, nil
+}
diff --git a/cmd/chain/time/process_internal_test.go b/cmd/chain/time/process_internal_test.go
new file mode 100644
index 0000000..7fb304c
--- /dev/null
+++ b/cmd/chain/time/process_internal_test.go
@@ -0,0 +1,103 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+import (
+	"context"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestProcess(t *testing.T) {
+	if os.Getenv("ETHDO_TEST_CONNECTION") == "" {
+		t.Skip("ETHDO_TEST_CONNECTION not configured; cannot run tests")
+	}
+
+	tests := []struct {
+		name     string
+		dataIn   *dataIn
+		expected *dataOut
+		err      string
+	}{
+		{
+			name: "Nil",
+			err:  "no data",
+		},
+		{
+			name: "Slot",
+			dataIn: &dataIn{
+				connection:               os.Getenv("ETHDO_TEST_CONNECTION"),
+				timeout:                  10 * time.Second,
+				allowInsecureConnections: true,
+				slot:                     "1",
+			},
+			expected: &dataOut{
+				epochStart: time.Unix(1606824023, 0),
+				epochEnd:   time.Unix(1606824407, 0),
+				slot:       1,
+				slotStart:  time.Unix(1606824035, 0),
+				slotEnd:    time.Unix(1606824047, 0),
+			},
+		},
+		{
+			name: "Epoch",
+			dataIn: &dataIn{
+				connection:               os.Getenv("ETHDO_TEST_CONNECTION"),
+				timeout:                  10 * time.Second,
+				allowInsecureConnections: true,
+				epoch:                    "2",
+			},
+			expected: &dataOut{
+				epoch:      2,
+				epochStart: time.Unix(1606824791, 0),
+				epochEnd:   time.Unix(1606825175, 0),
+				slot:       64,
+				slotStart:  time.Unix(1606824791, 0),
+				slotEnd:    time.Unix(1606824803, 0),
+			},
+		},
+		{
+			name: "Timestamp",
+			dataIn: &dataIn{
+				connection:               os.Getenv("ETHDO_TEST_CONNECTION"),
+				timeout:                  10 * time.Second,
+				allowInsecureConnections: true,
+				timestamp:                "2021-01-01T00:00:00",
+			},
+			expected: &dataOut{
+				epoch:      6862,
+				epochStart: time.Unix(1609459031, 0),
+				epochEnd:   time.Unix(1609459415, 0),
+				slot:       219598,
+				slotStart:  time.Unix(1609459199, 0),
+				slotEnd:    time.Unix(1609459211, 0),
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			res, err := process(context.Background(), test.dataIn)
+			if test.err != "" {
+				require.EqualError(t, err, test.err)
+			} else {
+				require.NoError(t, err)
+				require.Equal(t, test.expected, res)
+			}
+		})
+	}
+}
diff --git a/cmd/chain/time/run.go b/cmd/chain/time/run.go
new file mode 100644
index 0000000..52e5310
--- /dev/null
+++ b/cmd/chain/time/run.go
@@ -0,0 +1,50 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package chaintime
+
+import (
+	"context"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+)
+
+// Run runs the wallet create data command.
+func Run(cmd *cobra.Command) (string, error) {
+	ctx := context.Background()
+	dataIn, err := input(ctx)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to obtain input")
+	}
+
+	// Further errors do not need a usage report.
+	cmd.SilenceUsage = true
+
+	dataOut, err := process(ctx, dataIn)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to process")
+	}
+
+	if viper.GetBool("quiet") {
+		return "", nil
+	}
+
+	results, err := output(ctx, dataOut)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to obtain output")
+	}
+
+	return results, nil
+}
diff --git a/cmd/chaintime.go b/cmd/chaintime.go
new file mode 100644
index 0000000..2c79cb1
--- /dev/null
+++ b/cmd/chaintime.go
@@ -0,0 +1,60 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	chaintime "github.com/wealdtech/ethdo/cmd/chain/time"
+)
+
+var chainTimeCmd = &cobra.Command{
+	Use:   "time",
+	Short: "Obtain info about the chain at a given time",
+	Long: `Obtain info about the chain at a given time.  For example:
+
+    ethdo chain time --slot=12345`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		res, err := chaintime.Run(cmd)
+		if err != nil {
+			return err
+		}
+		if res != "" {
+			fmt.Print(res)
+		}
+		return nil
+	},
+}
+
+func init() {
+	chainCmd.AddCommand(chainTimeCmd)
+	chainFlags(chainTimeCmd)
+	chainTimeCmd.Flags().String("slot", "", "The slot for which to obtain information")
+	chainTimeCmd.Flags().String("epoch", "", "The epoch for which to obtain information")
+	chainTimeCmd.Flags().String("timestamp", "", "The timestamp for which to obtain information (format YYYY-MM-DDTHH:MM:SS)")
+}
+
+func chainTimeBindings() {
+	if err := viper.BindPFlag("slot", chainTimeCmd.Flags().Lookup("slot")); err != nil {
+		panic(err)
+	}
+	if err := viper.BindPFlag("epoch", chainTimeCmd.Flags().Lookup("epoch")); err != nil {
+		panic(err)
+	}
+	if err := viper.BindPFlag("timestamp", chainTimeCmd.Flags().Lookup("timestamp")); err != nil {
+		panic(err)
+	}
+}
diff --git a/cmd/root.go b/cmd/root.go
index 3640844..86deb64 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -74,6 +74,8 @@ func persistentPreRunE(cmd *cobra.Command, args []string) error {
 		attesterInclusionBindings()
 	case "block/info":
 		blockInfoBindings()
+	case "chain/time":
+		chainTimeBindings()
 	case "exit/verify":
 		exitVerifyBindings()
 	case "node/events":
@@ -88,6 +90,8 @@ func persistentPreRunE(cmd *cobra.Command, args []string) error {
 		validatorExitBindings()
 	case "validator/info":
 		validatorInfoBindings()
+	case "validator/keycheck":
+		validatorKeycheckBindings()
 	case "wallet/create":
 		walletCreateBindings()
 	case "wallet/import":
diff --git a/cmd/validator/keycheck/input.go b/cmd/validator/keycheck/input.go
new file mode 100644
index 0000000..4ecaf08
--- /dev/null
+++ b/cmd/validator/keycheck/input.go
@@ -0,0 +1,57 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validatorkeycheck
+
+import (
+	"context"
+	"time"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/viper"
+)
+
+type dataIn struct {
+	// System.
+	timeout time.Duration
+	quiet   bool
+	verbose bool
+	debug   bool
+	// Withdrawal credentials.
+	withdrawalCredentials string
+	// Operation.
+	mnemonic string
+	privKey  string
+}
+
+func input(ctx context.Context) (*dataIn, error) {
+	data := &dataIn{}
+
+	data.quiet = viper.GetBool("quiet")
+	data.verbose = viper.GetBool("verbose")
+	data.debug = viper.GetBool("debug")
+
+	// Withdrawal credentials.
+	data.withdrawalCredentials = viper.GetString("withdrawal-credentials")
+	if data.withdrawalCredentials == "" {
+		return nil, errors.New("withdrawal credentials are required")
+	}
+
+	data.mnemonic = viper.GetString("mnemonic")
+	data.privKey = viper.GetString("privkey")
+	if data.mnemonic == "" && data.privKey == "" {
+		return nil, errors.New("mnemonic or privkey is required")
+	}
+
+	return data, nil
+}
diff --git a/cmd/validator/keycheck/input_internal_test.go b/cmd/validator/keycheck/input_internal_test.go
new file mode 100644
index 0000000..969a681
--- /dev/null
+++ b/cmd/validator/keycheck/input_internal_test.go
@@ -0,0 +1,71 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validatorkeycheck
+
+import (
+	"context"
+	"testing"
+
+	"github.com/spf13/viper"
+	"github.com/stretchr/testify/require"
+)
+
+func TestInput(t *testing.T) {
+	tests := []struct {
+		name string
+		vars map[string]interface{}
+		res  *dataIn
+		err  string
+	}{
+		{
+			name: "WithdrawalCredentialsMissing",
+			vars: map[string]interface{}{},
+			err:  "withdrawal credentials are required",
+		},
+		{
+			name: "MnemonicAndPrivateKeyMissing",
+			vars: map[string]interface{}{
+				"withdrawal-credentials": "0x007e28dcf9029e8d92ca4b5d01c66c934e7f3110606f34ae3052cbf67bd3fc02",
+			},
+			err: "mnemonic or privkey is required",
+		},
+		{
+			name: "GoodWithMnemonic",
+			vars: map[string]interface{}{
+				"withdrawal-credentials": "0x007e28dcf9029e8d92ca4b5d01c66c934e7f3110606f34ae3052cbf67bd3fc02",
+				"mnemonic":               "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon art",
+			},
+			res: &dataIn{
+				withdrawalCredentials: "0x007e28dcf9029e8d92ca4b5d01c66c934e7f3110606f34ae3052cbf67bd3fc02",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			viper.Reset()
+
+			for k, v := range test.vars {
+				viper.Set(k, v)
+			}
+			res, err := input(context.Background())
+			if test.err != "" {
+				require.EqualError(t, err, test.err)
+			} else {
+				require.NoError(t, err)
+				require.Equal(t, test.res.withdrawalCredentials, res.withdrawalCredentials)
+			}
+		})
+	}
+}
diff --git a/cmd/validator/keycheck/output.go b/cmd/validator/keycheck/output.go
new file mode 100644
index 0000000..75d1e62
--- /dev/null
+++ b/cmd/validator/keycheck/output.go
@@ -0,0 +1,52 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validatorkeycheck
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"github.com/pkg/errors"
+)
+
+type dataOut struct {
+	debug   bool
+	quiet   bool
+	verbose bool
+	match   bool
+	path    string
+}
+
+func output(ctx context.Context, data *dataOut) (string, int, error) {
+	if data == nil {
+		return "", 1, errors.New("no data")
+	}
+
+	if data.quiet {
+		if !data.match {
+			os.Exit(1)
+		}
+		return "", 1, nil
+	}
+
+	if data.match {
+		if data.path == "" {
+			return "Withdrawal credentials confirmed", 0, nil
+		}
+		return fmt.Sprintf("Withdrawal credentials confirmed at path %s", data.path), 0, nil
+	} else {
+		return "Could not confirm withdrawal credentials with given information", 1, nil
+	}
+}
diff --git a/cmd/validator/keycheck/output_internal_test.go b/cmd/validator/keycheck/output_internal_test.go
new file mode 100644
index 0000000..912c38f
--- /dev/null
+++ b/cmd/validator/keycheck/output_internal_test.go
@@ -0,0 +1,81 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validatorkeycheck
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestOutput(t *testing.T) {
+	tests := []struct {
+		name     string
+		dataOut  *dataOut
+		exitCode int
+		expected []string
+		err      string
+	}{
+		{
+			name: "Nil",
+			err:  "no data",
+		},
+		{
+			name: "Not found",
+			dataOut: &dataOut{
+				match: false,
+			},
+			exitCode: 1,
+			expected: []string{
+				"Could not confirm withdrawal credentials with given information",
+			},
+		},
+		{
+			name: "Found",
+			dataOut: &dataOut{
+				match: true,
+			},
+			expected: []string{
+				"Withdrawal credentials confirmed",
+			},
+		},
+		{
+			name: "FoundWithPath",
+			dataOut: &dataOut{
+				match: true,
+				path:  "m/12381/3600/10/0",
+			},
+			expected: []string{
+				"Withdrawal credentials confirmed at path m/12381/3600/10/0",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			res, exitCode, err := output(context.Background(), test.dataOut)
+			if test.err != "" {
+				require.EqualError(t, err, test.err)
+			} else {
+				require.NoError(t, err)
+				require.Equal(t, test.exitCode, exitCode)
+				for _, expected := range test.expected {
+					require.True(t, strings.Contains(res, expected))
+				}
+			}
+		})
+	}
+}
diff --git a/cmd/validator/keycheck/process.go b/cmd/validator/keycheck/process.go
new file mode 100644
index 0000000..97f7b78
--- /dev/null
+++ b/cmd/validator/keycheck/process.go
@@ -0,0 +1,120 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validatorkeycheck
+
+import (
+	"bytes"
+	"context"
+	"encoding/hex"
+	"fmt"
+	"strings"
+
+	"github.com/pkg/errors"
+	"github.com/tyler-smith/go-bip39"
+	e2types "github.com/wealdtech/go-eth2-types/v2"
+	util "github.com/wealdtech/go-eth2-util"
+	"golang.org/x/text/unicode/norm"
+)
+
+func process(ctx context.Context, data *dataIn) (*dataOut, error) {
+	if data == nil {
+		return nil, errors.New("no data")
+	}
+
+	validatorWithdrawalCredentials, err := hex.DecodeString(strings.TrimPrefix(data.withdrawalCredentials, "0x"))
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to parse withdrawal credentials")
+	}
+
+	match := false
+	path := ""
+	if data.privKey != "" {
+		// Single private key to check.
+		keyBytes, err := hex.DecodeString(strings.TrimPrefix(data.privKey, "0x"))
+		if err != nil {
+			return nil, err
+		}
+		key, err := e2types.BLSPrivateKeyFromBytes(keyBytes)
+		if err != nil {
+			return nil, err
+		}
+
+		match, err = checkPrivKey(ctx, data.debug, validatorWithdrawalCredentials, key)
+		if err != nil {
+			return nil, err
+		}
+	} else {
+		// Mnemonic to check.
+		match, path, err = checkMnemonic(ctx, data.debug, validatorWithdrawalCredentials, data.mnemonic)
+	}
+
+	results := &dataOut{
+		debug:   data.debug,
+		quiet:   data.quiet,
+		verbose: data.verbose,
+		match:   match,
+		path:    path,
+	}
+
+	return results, nil
+}
+
+func checkPrivKey(ctx context.Context, debug bool, validatorWithdrawalCredentials []byte, key *e2types.BLSPrivateKey) (bool, error) {
+	pubKey := key.PublicKey()
+
+	withdrawalCredentials := util.SHA256(pubKey.Marshal())
+	withdrawalCredentials[0] = byte(0) // BLS_WITHDRAWAL_PREFIX
+
+	return bytes.Equal(withdrawalCredentials, validatorWithdrawalCredentials), nil
+}
+
+func checkMnemonic(ctx context.Context, debug bool, validatorWithdrawalCredentials []byte, mnemonic string) (bool, string, error) {
+	// If there are more than 24 words we treat the additional characters as the passphrase.
+	mnemonicParts := strings.Split(mnemonic, " ")
+	mnemonicPassphrase := ""
+	if len(mnemonicParts) > 24 {
+		mnemonic = strings.Join(mnemonicParts[:24], " ")
+		mnemonicPassphrase = strings.Join(mnemonicParts[24:], " ")
+	}
+	// Normalise the input.
+	mnemonic = string(norm.NFKD.Bytes([]byte(mnemonic)))
+	mnemonicPassphrase = string(norm.NFKD.Bytes([]byte(mnemonicPassphrase)))
+
+	if !bip39.IsMnemonicValid(mnemonic) {
+		return false, "", errors.New("mnemonic is invalid")
+	}
+
+	// Create seed from mnemonic and passphrase.
+	seed := bip39.NewSeed(mnemonic, mnemonicPassphrase)
+	// Check first 1024 indices.
+	for i := 0; i < 1024; i++ {
+		path := fmt.Sprintf("m/12381/3600/%d/0", i)
+		if debug {
+			fmt.Printf("Checking path %s\n", path)
+		}
+		key, err := util.PrivateKeyFromSeedAndPath(seed, path)
+		if err != nil {
+			return false, "", errors.Wrap(err, "failed to generate key")
+		}
+		match, err := checkPrivKey(ctx, debug, validatorWithdrawalCredentials, key)
+		if err != nil {
+			return false, "", errors.Wrap(err, "failed to match key")
+		}
+		if match {
+			return true, path, nil
+		}
+	}
+
+	return false, "", nil
+}
diff --git a/cmd/validator/keycheck/run.go b/cmd/validator/keycheck/run.go
new file mode 100644
index 0000000..f330814
--- /dev/null
+++ b/cmd/validator/keycheck/run.go
@@ -0,0 +1,51 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package validatorkeycheck
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+)
+
+// Run runs the wallet create data command.
+func Run(cmd *cobra.Command) (string, error) {
+	ctx := context.Background()
+	dataIn, err := input(ctx)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to obtain input")
+	}
+
+	// Further errors do not need a usage report.
+	cmd.SilenceUsage = true
+
+	dataOut, err := process(ctx, dataIn)
+	if err != nil {
+		return "", err
+	}
+
+	results, exitCode, err := output(ctx, dataOut)
+	if err != nil {
+		return "", err
+	}
+	if exitCode != 0 {
+		fmt.Println(results)
+		os.Exit(exitCode)
+	}
+
+	return results, nil
+}
diff --git a/cmd/validatorkeycheck.go b/cmd/validatorkeycheck.go
new file mode 100644
index 0000000..fccd4a2
--- /dev/null
+++ b/cmd/validatorkeycheck.go
@@ -0,0 +1,67 @@
+// Copyright © 2021 Weald Technology Trading
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
+	validatorkeycheck "github.com/wealdtech/ethdo/cmd/validator/keycheck"
+)
+
+var validatorKeycheckCmd = &cobra.Command{
+	Use:   "keycheck",
+	Short: "Check that the withdrawal credentials for a validator matches the given key.",
+	Long: `Check that the withdrawal credentials for a validator matches the given key.  For example:
+
+    ethdo validator keycheck --withdrawal-credentials=0x007e28dcf9029e8d92ca4b5d01c66c934e7f3110606f34ae3052cbf67bd3fc02 --privkey=0x1b46e61babc7a6a0fbfe8e416de3c71f85e367f24e0bfcb12e57adb11117662c
+
+A mnemonic can be used in place of a private key, in which case the first 1,024 indices of the standard withdrawal key path will be scanned for a matching key.
+
+In quiet mode this will return 0 if the withdrawal credentials match the key, otherwise 1.`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		res, err := validatorkeycheck.Run(cmd)
+		if err != nil {
+			return err
+		}
+		if viper.GetBool("quiet") {
+			return nil
+		}
+		if res != "" {
+			fmt.Println(res)
+		}
+		return nil
+	},
+}
+
+func init() {
+	validatorCmd.AddCommand(validatorKeycheckCmd)
+	validatorFlags(validatorKeycheckCmd)
+	validatorKeycheckCmd.Flags().String("withdrawal-credentials", "", "Withdrawal credentials to check (can run offline)")
+	validatorKeycheckCmd.Flags().String("mnemonic", "", "Mnemonic from which to generate withdrawal credentials")
+	validatorKeycheckCmd.Flags().String("privkey", "", "Private key from which to generate withdrawal credentials")
+}
+
+func validatorKeycheckBindings() {
+	if err := viper.BindPFlag("withdrawal-credentials", validatorKeycheckCmd.Flags().Lookup("withdrawal-credentials")); err != nil {
+		panic(err)
+	}
+	if err := viper.BindPFlag("mnemonic", validatorKeycheckCmd.Flags().Lookup("mnemonic")); err != nil {
+		panic(err)
+	}
+	if err := viper.BindPFlag("privkey", validatorKeycheckCmd.Flags().Lookup("privkey")); err != nil {
+		panic(err)
+	}
+}
diff --git a/cmd/version.go b/cmd/version.go
index 61f246a..1042f1d 100644
--- a/cmd/version.go
+++ b/cmd/version.go
@@ -24,7 +24,7 @@ import (
 
 // ReleaseVersion is the release version of the codebase.
 // Usually overrideen by tag names when building binaries.
-var ReleaseVersion = "local build (latest release 1.7.5)"
+var ReleaseVersion = "local build (latest release 1.8.0)"
 
 // versionCmd represents the version command
 var versionCmd = &cobra.Command{
diff --git a/docs/usage.md b/docs/usage.md
index 6462744..2c01f8f 100644
--- a/docs/usage.md
+++ b/docs/usage.md
@@ -325,6 +325,23 @@ Prior justified epoch: 3
 Prior justified epoch distance: 4
 ```
 
+#### `time`
+
+`ethdo chain time` calculates the time period of Ethereum 2 epochs and slots.  Options include:
+  - `epoch` show epoch and slot times for the given epoch
+  - `slot` show epoch and slot times for the given slot
+  - `timestamp` show epoch and slot times for the given timestamp
+
+```sh
+$ ethdo chain time --epoch=1234
+Epoch 1234
+  Epoch start 2020-12-06 23:37:59
+  Epoch end 2020-12-06 23:44:23
+Slot 39488
+  Slot start 2020-12-06 23:37:59
+  Slot end 2020-12-06 23:38:11
+```
+
 ### `deposit` comands
 
 Deposit commands focus on information about deposit data information in a JSON file generated by the `ethdo validator depositdata` command.
@@ -471,6 +488,18 @@ Balance:           3.201850307 Ether
 Effective balance: 3.1 Ether
 ```
 
+#### `keycheck`
+
+`ethdo validator keycheck` checks if a given key matches a validator's withdrawal credentials.  Options include:
+  - `withdrawal-credentials` the withdrawal credentials against which to match
+  - `privkey` the private key used to generat matching withdrawal credentials
+  - `mnemonic` the mnemonic used to generate matching withdrawal credentials
+
+```sh
+$ ethdo validator keycheck --withdrawal-credentials=0x007e28dcf9029e8d92ca4b5d01c66c934e7f3110606f34ae3052cbf67bd3fc02 --mnemonic='abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon art'
+Withdrawal credentials confirmed at path m/12381/3600/10/0
+```
+
 ### `attester` commands
 
 Attester commands focus on Ethereum 2 validators' actions as attesters.