diff --git a/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptPubKey.scala b/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptPubKey.scala
index 8730efea06..871ca5c30e 100644
--- a/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptPubKey.scala
+++ b/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptPubKey.scala
@@ -1176,15 +1176,21 @@ object WitnessScriptPubKey extends ScriptFactory[WitnessScriptPubKey] {
     // ScriptConstantImpl(ByteVector(37 bytes, 0x0021020afd6012af90835558c68365a370b7e6cd1c0d4664a8656c8c7847185cb5db6651ae)))
 
     //we can also have a LockTimeScriptPubKey with a nested 0 public key multisig script, need to check that as well
-    val bytes = BytesUtil.toByteVector(asm)
 
+    //it turns out this method gets called a lot when we attempt
+    //to type check spks, so let's do a cheap check before deserializing
+    //everything to a byte vector which is expensive
     val firstOp = asm.headOption
-    if (bytes.size < 4 || bytes.size > 42) false
-    else if (!validWitVersions.contains(firstOp.getOrElse(OP_1NEGATE))) false
-    else if (MultiSignatureScriptPubKey.isValidAsm(asm)) false
-    else if (LockTimeScriptPubKey.isValidAsm(asm)) false
-    else if (asm(1).toLong + 2 == bytes.size) true
-    else false
+    if (!validWitVersions.contains(firstOp.getOrElse(OP_1NEGATE))) {
+      false
+    } else {
+      val bytes = BytesUtil.toByteVector(asm)
+      if (bytes.length < 4 || bytes.length > 42) false
+      else if (MultiSignatureScriptPubKey.isValidAsm(asm)) false
+      else if (LockTimeScriptPubKey.isValidAsm(asm)) false
+      else if (asm(1).toLong + 2 == bytes.size) true
+      else false
+    }
   }
 }
 
diff --git a/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptSignature.scala b/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptSignature.scala
index 23a93fafc5..902112e41c 100644
--- a/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptSignature.scala
+++ b/core/src/main/scala/org/bitcoins/core/protocol/script/ScriptSignature.scala
@@ -254,33 +254,41 @@ object P2SHScriptSignature extends ScriptFactory[P2SHScriptSignature] {
 
   /** Detects if the given script token is a redeem script */
   def isRedeemScript(token: ScriptToken): Boolean = {
-    val redeemScript: ScriptPubKey = parseRedeemScript(token)
-
-    def isStandardNonP2SH(
-        spk: ScriptPubKey,
-        isRecursiveCall: Boolean): Boolean = {
-      spk match {
-        case _: P2PKHScriptPubKey | _: MultiSignatureScriptPubKey |
-            _: P2PKScriptPubKey | _: P2PKWithTimeoutScriptPubKey |
-            _: WitnessScriptPubKeyV0 | _: UnassignedWitnessScriptPubKey =>
-          true
-        case EmptyScriptPubKey => isRecursiveCall // Fine if nested
-        case conditional: ConditionalScriptPubKey =>
-          isStandardNonP2SH(conditional.firstSPK,
-                            isRecursiveCall = true) && isStandardNonP2SH(
-            conditional.secondSPK,
-            isRecursiveCall = true)
-        case locktime: LockTimeScriptPubKey =>
-          Try(locktime.locktime).isSuccess &&
-            isStandardNonP2SH(locktime.nestedScriptPubKey,
-                              isRecursiveCall = true)
-        case _: NonStandardScriptPubKey | _: WitnessCommitment |
-            _: P2SHScriptPubKey =>
-          false
-      }
+    token match {
+      case _: ScriptNumberOperation | _: ScriptOperation =>
+        //more cheap checks, we can't have a redeemScript
+        //if the token is OP_0/OP_1/OP_CHECKSIG etc
+        false
+      case constant: ScriptConstant =>
+        val redeemScript: ScriptPubKey = parseRedeemScript(constant)
+        isStandardNonP2SH(redeemScript, isRecursiveCall = false)
     }
+  }
 
-    isStandardNonP2SH(redeemScript, isRecursiveCall = false)
+  private def isStandardNonP2SH(
+      spk: ScriptPubKey,
+      isRecursiveCall: Boolean): Boolean = {
+    spk match {
+      case _: P2PKHScriptPubKey | _: MultiSignatureScriptPubKey |
+          _: P2PKScriptPubKey | _: P2PKWithTimeoutScriptPubKey |
+          _: WitnessScriptPubKeyV0 | _: UnassignedWitnessScriptPubKey =>
+        true
+      case EmptyScriptPubKey => isRecursiveCall // Fine if nested
+      case conditional: ConditionalScriptPubKey =>
+        isStandardNonP2SH(conditional.firstSPK,
+                          isRecursiveCall = true) && isStandardNonP2SH(
+          conditional.secondSPK,
+          isRecursiveCall = true)
+      case locktime: LockTimeScriptPubKey =>
+        if (Try(locktime.locktime).isSuccess) {
+          isStandardNonP2SH(locktime.nestedScriptPubKey, isRecursiveCall = true)
+        } else {
+          false
+        }
+      case _: NonStandardScriptPubKey | _: WitnessCommitment |
+          _: P2SHScriptPubKey =>
+        false
+    }
   }
 
   /** Parses a redeem script from the given script token */