diff --git a/lib/bcoin/script.js b/lib/bcoin/script.js
index cda6da43..4604ecfc 100644
--- a/lib/bcoin/script.js
+++ b/lib/bcoin/script.js
@@ -788,7 +788,7 @@ script.standard = function standard(s) {
     || (script.isPubkeyhash(s) && 'pubkeyhash')
     || (script.isMultisig(s) && 'multisig')
     || (script.isScripthash(s) && 'scripthash')
-    || (script.isNullData(s) && 'colored')
+    || (script.isColored(s) && 'colored')
     || 'nonstandard';
 };
 
@@ -800,6 +800,23 @@ script.lockTime = function lockTime(s) {
     && new bn(s[0]);
 };
 
+script.isPubkey = function isPubkey(s, hash) {
+  if (script.lockTime(s))
+    s = s.slice(3);
+
+  if (s.length !== 2)
+    return false;
+
+  var match = Array.isArray(s[0]) && s[1] === 'checksig';
+  if (!match)
+    return false;
+
+  if (hash)
+    return utils.isEqual(s[0], hash);
+  else
+    return s[0];
+};
+
 script.isPubkeyhash = function isPubkeyhash(s, hash) {
   if (script.lockTime(s))
     s = s.slice(3);
@@ -821,23 +838,6 @@ script.isPubkeyhash = function isPubkeyhash(s, hash) {
     return s[2];
 };
 
-script.isPubkey = function isPubkey(s, hash) {
-  if (script.lockTime(s))
-    s = s.slice(3);
-
-  if (s.length !== 2)
-    return false;
-
-  var match = Array.isArray(s[0]) && s[1] === 'checksig';
-  if (!match)
-    return false;
-
-  if (hash)
-    return utils.isEqual(s[0], hash);
-  else
-    return s[0];
-};
-
 script.isMultisig = function isMultisig(s, key) {
   if (script.lockTime(s))
     s = s.slice(3);
@@ -880,14 +880,6 @@ script.isMultisig = function isMultisig(s, key) {
   }).length;
 };
 
-script.isPubkeyhashInput = function isPubkeyhashInput(s) {
-  if (s.length !== 2)
-    return false;
-
-  return 9 <= s[0].length && s[0].length <= 73 &&
-         33 <= s[1].length && s[1].length <= 65;
-};
-
 script.isScripthash = function isScripthash(s, hash) {
   if (script.lockTime(s))
     s = s.slice(3);
@@ -909,7 +901,7 @@ script.isScripthash = function isScripthash(s, hash) {
   return true;
 };
 
-script.isNullData = function isNullData(s) {
+script.isColored = function isColored(s) {
   if (s.length !== 2)
     return false;
 
@@ -918,6 +910,64 @@ script.isNullData = function isNullData(s) {
          s[1].length <= 40;
 };
 
+script.colored = function colored(s) {
+  if (!script.isColored(s))
+    return false;
+
+  return s[1];
+};
+
+script.isPubkeyInput = function isPubkeyInput(s) {
+  if (s.length !== 1 || !Array.isArray(s[0]))
+    return false;
+
+  return 9 <= s[0].length && s[0].length <= 73;
+};
+
+script.isPubkeyhashInput = function isPubkeyhashInput(s) {
+  if (s.length !== 2 || !Array.isArray(s[0]) || !Array.isArray(s[1]))
+    return false;
+
+  return 9 <= s[0].length && s[0].length <= 73 &&
+         33 <= s[1].length && s[1].length <= 65;
+};
+
+script.isMultisigInput = function isMultisigInput(s) {
+  if (s.length < 3)
+    return false;
+
+  if (!Array.isArray(s[0]) || s[0].length !== 0)
+    return false;
+
+  for (var i = 1; i < s.length; i++) {
+    var ret = 9 <= s[i].length && s[i].length <= 73;
+    if (!ret)
+      return false;
+  }
+
+  return true;
+};
+
+script.isScripthashInput = function isScripthashInput(s) {
+  if (s.length < 4)
+    return false;
+
+  if (!Array.isArray(s[0]) || s[0].length !== 0)
+    return false;
+
+  for (var i = 1; i < s.length - 1; i++) {
+    var ret = Array.isArray(s[i]) && 9 <= s[i].length && s[i].length <= 73;
+    if (!ret)
+      return false;
+  }
+
+  var r = Array.isArray(s[s.length - 1]) && s[s.length - 1];
+  if (r[r.length - 1] !== constants.opcodes.checkmultisig)
+    return false;
+
+  return true;
+};
+
 // https://github.com/bitcoin/bips/blob/master/bip-0066.mediawiki
 /**
  * A canonical signature exists of: <30> <total len> <02> <len R> <R> <02> <len S> <S> <hashtype>
diff --git a/test/script-test.js b/test/script-test.js
index e3a91f8e..cb036ce5 100644
--- a/test/script-test.js
+++ b/test/script-test.js
@@ -42,7 +42,7 @@ describe('Script', function() {
     var hex = '6a28590c080112220a1b353930632e6f7267282a5f5e294f7665726c6179404f7261636c65103b1a010c'
     var encoded = bcoin.utils.toArray(hex, 'hex')
     var decoded = bcoin.script.decode(encoded);
-    assert(bcoin.script.isNullData(decoded))
+    assert(bcoin.script.isColored(decoded))
   })
 
   it('should handle if statements correctly', function () {