diff --git a/lib/modules/profiler/fuzzer.js b/lib/modules/profiler/fuzzer.js
index 6e11e8e1..22d2ca90 100644
--- a/lib/modules/profiler/fuzzer.js
+++ b/lib/modules/profiler/fuzzer.js
@@ -1,5 +1,4 @@
 const utils = require('web3-utils');
-
 const u = require('../../utils/utils.js');
 
 // generates random inputs based on the inputs of an ABI
@@ -11,7 +10,7 @@ class ContractFuzzer {
   }
 
   // main function to call, takes in iteration number and a contract and returns a map object
-  // composed of method names -> fuzzed inputs. 
+  // composed of method names -> fuzzed inputs.
   generateFuzz(iterations, contract) {
     const self = this;
     let fuzzMap = {};
@@ -52,10 +51,10 @@ class ContractFuzzer {
       case kind == "bool":
         return self.generateRandomBool();
       case kind == "uint" || kind == "int":
-        return self.generateRandomInt(size);
-      case kind === "bytes" && size !== undefined:
-        return self.generateRandomStaticBytes(size);
-      case kind === "string" || kind === "bytes":
+        return self.generateRandomInt(size || 256);
+      case kind === "bytes":
+        return self.generateRandomStaticBytes(size || 32);
+      case kind === "string":
         return self.generateRandomDynamicType();
       case kind === "address":
         return self.generateRandomAddress();
@@ -79,11 +78,11 @@ class ContractFuzzer {
   }
 
   generateRandomStaticBytes(size) {
-    return utils.randomHex(size);
+    return utils.randomHex(parseInt(size, 10));
   }
 
   generateRandomInt(size) {
-    return utils.toBN(utils.randomHex(size / 8));
+    return utils.toBN(utils.randomHex(parseInt(size, 10) / 8));
   }
 
   generateRandomAddress() {