diff --git a/benchmark/zlib/creation.js b/benchmark/zlib/creation.js
index 5046ef50ecff06..4984bf1a86b755 100644
--- a/benchmark/zlib/creation.js
+++ b/benchmark/zlib/creation.js
@@ -10,14 +10,13 @@ const bench = common.createBenchmark(main, {
   n: [5e5]
 });
 
-function main(conf) {
-  const n = +conf.n;
-  const fn = zlib[`create${conf.type}`];
+function main({ n, type, options }) {
+  const fn = zlib[`create${type}`];
   if (typeof fn !== 'function')
     throw new Error('Invalid zlib type');
   var i = 0;
 
-  if (conf.options === 'true') {
+  if (options === 'true') {
     const opts = {};
     bench.start();
     for (; i < n; ++i)
diff --git a/benchmark/zlib/deflate.js b/benchmark/zlib/deflate.js
index 00993b64462539..5e86d659803747 100644
--- a/benchmark/zlib/deflate.js
+++ b/benchmark/zlib/deflate.js
@@ -8,10 +8,8 @@ const bench = common.createBenchmark(main, {
   n: [4e5]
 });
 
-function main(conf) {
-  const n = +conf.n;
-  const method = conf.method;
-  const chunk = Buffer.alloc(+conf.inputLen, 'a');
+function main({ n, method, inputLen }) {
+  const chunk = Buffer.alloc(inputLen, 'a');
 
   var i = 0;
   switch (method) {