diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index 063b5765..716c5eb8 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -157,7 +157,7 @@ utils.toBase58 = function toBase58(buf) {
   }
 
   i = size - length;
-  while (b58[i] === 0)
+  while (i < b58.length && b58[i] === 0)
     i++;
 
   for (j = 0; j < zeroes; j++)
@@ -199,7 +199,7 @@ utils.fromBase58 = function fromBase58(str) {
   }
 
   i = 0;
-  while (b256[i] === 0)
+  while (i < b256.length && b256[i] === 0)
     i++;
 
   out = new Buffer(zeroes + (b256.length - i));
@@ -207,8 +207,8 @@ utils.fromBase58 = function fromBase58(str) {
   for (j = 0; j < zeroes; j++)
     out[j] = 0;
 
-  for (; i < b256.length; i++)
-    out[i] = b256[i];
+  while (i < b256.length)
+    out[j++] = b256[i++];
 
   return out;
 };