diff --git a/benchmark/child_process/child-process-read-ipc.js b/benchmark/child_process/child-process-read-ipc.js
index 827f75b1e54bd1..280505026cd02e 100644
--- a/benchmark/child_process/child-process-read-ipc.js
+++ b/benchmark/child_process/child-process-read-ipc.js
@@ -13,7 +13,7 @@ if (process.argv[2] === 'child') {
   const bench = common.createBenchmark(main, {
     len: [
       64, 256, 1024, 4096, 16384, 65536,
-      65536 << 4, 65536 << 8,
+      65536 << 4, 65536 << 6 - 1,
     ],
     dur: [5]
   });