Benchmark: Object for...in vs for...index 2【no hasOwn】

HTML Preparation code:

<!--your preparation HTML code goes here-->

Script Preparation code:

// 生成测试对象
const createTestObject = (size) => {
  const obj = {};
  for (let i = 0; i < size; i++) {
    obj[`key${i}`] = i;
  }
  return obj;
};

// 测试 for...in
function testForIn(obj) {
  const start = performance.now();
  for (const key in obj) {
      const value = obj[key];
  }
  return performance.now() - start;
}

// 测试 Object.keys + for
function testObjectKeysFor(obj) {
  const start = performance.now();
  const keys = Object.keys(obj);
  for (let i = 0; i < keys.length; i++) {
    const key = keys[i];
    const value = obj[key];
  }
  return performance.now() - start;
}

// 运行测试
const obj = createTestObject(10);

Tests:

forIn
testForIn(obj)
forIndex
testObjectKeysFor(obj)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
forIn
forIndex

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Android 15; Mobile; rv:148.0) Gecko/148.0 Firefox/148.0

Browser/OS: Firefox Mobile 148 on Android

View result in a separate tab

forIn

3.9M/s

forIndex

3.8M/s

View exact numbers

Test name	Executions per second
✓ forIn	3,905,115 Ops/sec
forIndex	3,758,336 Ops/sec

Object for...in vs for...index 2【no hasOwn】 (version: 1) Benchmark.js

Comparing performance of: `forIn vs forIndex`

Created: 6 months ago by: Guest

Go to the latest result

forIn

forIndex

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Object for...in vs for...index 2【no hasOwn】 (version: 1) Benchmark.js

Comparing performance of: forIn vs forIndex

Created: 6 months ago by: Guest

Go to the latest result

forIn

forIndex

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `forIn vs forIndex`