diff --git a/README.md b/README.md
index aea4823..2c87bcc 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ A lightweight turing-incomplete assembly language for STARK proofs. Designed to
 
 Each line of a circuitvm `asm` file should contain an opcode, followed by registers to operate on. Each argument should be separated by exactly 1 space. Numbers may be prefixed by `0x` for hex, or written normally for decimal.
 
-Lines starting with `#` or containing only whitespace are ignored.
+Lines starting with `;` or containing only whitespace are ignored.
 
 ## Opcodes
 
diff --git a/src/compiler.mjs b/src/compiler.mjs
index 8587039..b5fab2a 100644
--- a/src/compiler.mjs
+++ b/src/compiler.mjs
@@ -104,14 +104,15 @@ export function compile(asm) {
   const steps = asm
     .split('\n')
     .filter(line => {
-      if (line.startsWith('#')) return false
+      if (line.trim().startsWith(';')) return false
       if (line.trim().length === 0) return false
       return true
     })
     .map(line => line.trim())
     .map(line => line.split(' '))
     .map((operation, i) => {
-      const [ op, ...args ] = operation
+      const commentIndex = operation.indexOf(';')
+      const [ op, ...args ] = commentIndex >= 0 ? operation.slice(0, commentIndex) : operation
       if (!validOperations[op]) {
         throw new Error(`Invalid op "${op}"`)
       }
diff --git a/test/example1.asm b/test/example1.asm
index 804e01b..3da4526 100644
--- a/test/example1.asm
+++ b/test/example1.asm
@@ -1,16 +1,16 @@
-# a simple repeated squaring program
+; a simple repeated squaring program
 set 0x0 100
-# calculate 100^4
+; calculate 100^4
 mul 0x1 0x0 0x0
 mul 0x1 0x0 0x1
 mul 0x1 0x0 0x1
-# make a public signal and assert its expected value
+; make a public signal and assert its expected value
 out 0x1 100000000
-# now calculate 200^4
+; now calculate 200^4
 set 0x0 200
 mul 0x1 0x0 0x0
 mul 0x1 0x0 0x1
 mul 0x1 0x0 0x1
-# and output
+; and output
 out 0x1 1600000000
-# registers can be reused after an output is marked
+; registers can be reused after an output is marked