Benchmark: Object.keys vs for...in

Script Preparation code:

var users = {
  user1: {
    name: "John1",
    age: 30
  },
  user2: {
    name: "John2",
    age: 20
  },
  user3: {
    name: "John3",
    age: 25
  },
  user4: {
    name: "John4",
    age: 50
  }
};

Tests:

Object.keys
Object.keys(users).forEach(userId => console.log(users[userId]));
for...in
for (const userId in users) { if (users.hasOwnProperty(userId)) { console.log(users[userId]) } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.keys
for...in

Fastest: N/A

Slowest: N/A

ⓘ Get performance results from real users on your website with Request Metrics.

Website Performance Monitoring by Request Metrics

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.121 Safari/537.36

Browser/OS: Chrome 85 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Object.keys	11315.5 Ops/sec
for...in	12771.6 Ops/sec

Object.keys vs for...in (version: 0)

Comparing performance of: Object.keys vs for...in

Created: 3 years ago by: Guest

Jump to the latest result

Object.keys

for...in

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A