diff --git a/packages/livedata/base64.js b/packages/livedata/base64.js
new file mode 100644
index 0000000000..d46200d73d
--- /dev/null
+++ b/packages/livedata/base64.js
@@ -0,0 +1,127 @@
+// Base 64 encoding
+
+(function () {
+
+var BASE_64_CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+
+var BASE_64_VALS = {};
+
+for (var i = 0; i < BASE_64_CHARS.length; i++) {
+  BASE_64_VALS[BASE_64_CHARS.substr(i, 1)] = i;
+};
+
+Meteor._base64Encode = function (array) {
+  var answer = [];
+  var a = null;
+  var b = null;
+  var c = null;
+  var d = null;
+  for (var i = 0; i < array.length; i++) {
+    switch (i % 3) {
+    case 0:
+      a = (array[i] >> 2) & 0x3F;
+      b = (array[i] & 0x03) << 4;
+      break;
+    case 1:
+      b = b | (array[i] >> 4) & 0xF;
+      c = (array[i] & 0xF) << 2;
+      break;
+    case 2:
+      c = c | (array[i] >> 6) & 0x03;
+      d = array[i] & 0x3F;
+      answer.push(getChar(a));
+      answer.push(getChar(b));
+      answer.push(getChar(c));
+      answer.push(getChar(d));
+      a = null;
+      b = null;
+      c = null;
+      d = null;
+      break;
+    }
+  }
+  if (a != null) {
+    answer.push(getChar(a));
+    answer.push(getChar(b));
+    if (c == null)
+      answer.push('=');
+    else
+      answer.push(getChar(c));
+    if (d == null)
+      answer.push('=');
+  }
+  return answer.join("");
+};
+
+var getChar = function (val) {
+  return BASE_64_CHARS.substr(val, 1);
+};
+
+var getVal = function (ch) {
+  if (ch === '=') {
+    return -1;
+  }
+  return BASE_64_VALS[ch];
+};
+
+var newBuffer = function (len) {
+  if (typeof Uint8Array === 'undefined' || typeof ArrayBuffer === 'undefined') {
+    var ret = [];
+    for (var i = 0; i < len; i++) {
+      ret.push(0);
+    }
+    ret.$Uint8ArrayPolyfill = true;
+    return ret;
+  }
+  return new Uint8Array(new ArrayBuffer(len));
+};
+
+Meteor._base64Decode = function (str) {
+  var len = Math.floor((str.length*3)/4);
+  if (str.substr(str.length - 1) == '=') {
+    len--;
+    if (str.substr(str.length - 2, 1) == '=')
+      len--;
+  }
+  var arr = newBuffer(len);
+
+  var one = null;
+  var two = null;
+  var three = null;
+
+  var j = 0;
+
+  for (var i = 0; i < str.length; i++) {
+    var c = str.substr(i, 1);
+    var v = getVal(c);
+    switch (i % 4) {
+    case 0:
+      if (v < 0)
+        throw new Error('invalid base64 string');
+      one = v << 2;
+      break;
+    case 1:
+      if (v < 0)
+        throw new Error('invalid base64 string');
+      one = one | (v >> 4);
+      arr[j++] = one;
+      two = (v & 0x0F) << 4;
+      break;
+    case 2:
+      if (v > 0) {
+        two = two | (v >> 2);
+        arr[j++] = two;
+        three = (v & 0x03) << 6;
+      }
+      break;
+    case 3:
+      if (v > 0) {
+        arr[j++] = three | v;
+      }
+      break;
+    }
+  }
+  return arr;
+};
+
+})();
diff --git a/packages/livedata/livedata_common.js b/packages/livedata/livedata_common.js
index e1d49fafbc..cb8f8664c9 100644
--- a/packages/livedata/livedata_common.js
+++ b/packages/livedata/livedata_common.js
@@ -99,6 +99,21 @@ var builtinConverters = [
       return new Date(obj.$date);
     }
   },
+  { // Binary
+    matchJSONValue: function (obj) {
+      return _.has(obj, '$binary') && _.size(obj) === 1;
+    },
+    matchObject: function (obj) {
+      return typeof Uint8Array !== 'undefined' && obj instanceof Uint8Array
+        || (obj && _.has(obj, '$Uint8ArrayPolyfill'));
+    },
+    toJSONValue: function (obj) {
+      return {$binary: Meteor._base64Encode(obj)};
+    },
+    fromJSONValue: function (obj) {
+      return Meteor._base64Decode(obj.$binary);
+    }
+  },
   { // Literal
     matchJSONValue: function (obj) {
       return _.has(obj, '$literal') && _.size(obj) === 1;
diff --git a/packages/livedata/package.js b/packages/livedata/package.js
index a741f1790f..7476a600d7 100644
--- a/packages/livedata/package.js
+++ b/packages/livedata/package.js
@@ -13,6 +13,7 @@ Package.on_use(function (api) {
 
   api.add_files('writefence.js', 'server');
   api.add_files('crossbar.js', 'server');
+  api.add_files('base64.js', ['client', 'server']);
 
   api.add_files('livedata_common.js', ['client', 'server']);
 
@@ -35,4 +36,5 @@ Package.on_test(function (api) {
   api.add_files('livedata_tests.js', ['client', 'server']);
   api.add_files('livedata_test_service.js', ['client', 'server']);
   api.add_files('session_view_tests.js', ['server']);
+  api.add_files('test_base64.js', ['client', 'server']);
 });
diff --git a/packages/livedata/test_base64.js b/packages/livedata/test_base64.js
new file mode 100644
index 0000000000..99c89c8e2c
--- /dev/null
+++ b/packages/livedata/test_base64.js
@@ -0,0 +1,47 @@
+(function () {
+
+  var asciiToArray = function (str) {
+    var arr = new Uint8Array(new ArrayBuffer(str.length));
+    for (var i = 0; i < str.length; i++) {
+      var c = str.charCodeAt(i);
+      if (c > 0xFF) {
+        throw new Error("Not ascii");
+      }
+      arr[i] = c;
+    }
+    return arr;
+  };
+
+  var arrayToAscii = function (arr) {
+    var res = [];
+    for (var i = 0; i < arr.length; i++) {
+      res.push(String.fromCharCode(arr[i]));
+    }
+    return res.join("");
+  };
+
+  Tinytest.add("base64 - testing the test", function (test) {
+    test.equal(arrayToAscii(asciiToArray("The quick brown fox jumps over the lazy dog")),
+               "The quick brown fox jumps over the lazy dog");
+  });
+
+  Tinytest.add("base64 - empty", function (test) {
+    test.equal(Meteor._base64Encode(new Uint8Array(new ArrayBuffer(0))), "");
+    test.equal(Meteor._base64Decode(""), new Uint8Array(new ArrayBuffer(0)));
+  });
+
+
+  Tinytest.add("base64 - wikipedia examples", function (test) {
+    var tests = [
+      {txt: "pleasure.", res: "cGxlYXN1cmUu"},
+      {txt: "leasure.", res: "bGVhc3VyZS4="},
+      {txt: "easure.", res: "ZWFzdXJlLg=="},
+      {txt: "asure.", res: "YXN1cmUu"},
+      {txt: "sure.", res: "c3VyZS4="}
+    ];
+    _.each(tests, function(t) {
+      test.equal(Meteor._base64Encode(asciiToArray(t.txt)), t.res);
+      test.equal(arrayToAscii(Meteor._base64Decode(t.res)), t.txt);
+    });
+  });
+})();