Benchmark: NodeList For vs Foreach

Script Preparation code:

var div = document.createElement('div');
for (let i = 0; i < 1000; i++) {
    div.insertAdjacentHTML('beforeend', `<span>span-${i}<span>`);
}

var list = div.querySelectorAll('span');

Tests:

Default For
for(let i = 0; i < list.length; i++) { list[i].setAttribute('tabindex', '-1'); }
For with length caching
list.forEach(item =>{ item.setAttribute('tabindex', '-1'); });
forEach
for(let i = 0, lenght = list.lenght ; i < length; i++) { list[i].setAttribute('tabindex', '-1'); }

Historical Performance Data aggregated from 6 community runs

Desktop Results:

Chrome 6 runs

forEach

5.1M/s

Default For

3K/s

For with length caching

2K/s

Fastest: forEach (2597.2x faster)

View exact numbers

✓ forEach: 5,108,328 ops/sec
• Default For: 2,522 ops/sec
• For with length caching: 1,967 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Default For
For with length caching
forEach

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:149.0) Gecko/20100101 Firefox/149.0

Browser/OS: Firefox 149 on Windows

View result in a separate tab

forEach

4.3M/s

Default For

2K/s

For with length caching

2K/s

View exact numbers

Test name	Executions per second
✓ forEach	4,347,238 Ops/sec
Default For	1,632 Ops/sec
For with length caching	1,613 Ops/sec

NodeList For vs Foreach (version: 0) Benchmark.js

Comparing performance of: `Default For vs For with length caching vs forEach`

Created: 6 years ago by: Guest

Go to the latest result

Default For

For with length caching

forEach

Historical Performance Data aggregated from 6 community runs

Desktop Results:

Chrome 6 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

NodeList For vs Foreach (version: 0) Benchmark.js

Comparing performance of: Default For vs For with length caching vs forEach

Created: 6 years ago by: Guest

Go to the latest result

Default For

For with length caching

forEach

Historical Performance Data aggregated from 6 community runs

Desktop Results:

Chrome 6 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `Default For vs For with length caching vs forEach`