diff --git a/lib/modules/profiler/fuzzer.js b/lib/modules/profiler/fuzzer.js
index 22d2ca90..4589dda8 100644
--- a/lib/modules/profiler/fuzzer.js
+++ b/lib/modules/profiler/fuzzer.js
@@ -82,7 +82,7 @@ class ContractFuzzer {
   }
 
   generateRandomInt(size) {
-    return utils.toBN(utils.randomHex(parseInt(size, 10) / 8));
+    return utils.toBN(utils.randomHex(parseInt(size, 10) / 8)).toString();
   }
 
   generateRandomAddress() {