Benchmark: reduce.concat() vs flat() vs concat + spread vs reduce + spread

Tests:

reduce + Array.prototype.concat
var params = [[ 1, 2 ], [ "hello", true, 7 ]]; var other = params.reduce((acc, val) => acc.concat(val), []);
Array.prototype.flat
var params = [[ 1, 2 ], [ "hello", true, 7 ]]; var other = params.flat();
concat + spread
var params = [[ 1, 2 ], [ "hello", true, 7 ]]; var other = [].concat(...params);
reduce + spread
var params = [[ 1, 2 ], [ "hello", true, 7 ]]; var other = params.reduce((acc, val) => { acc.push(...val); return acc; }, []);

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

reduce + spread

17.0M/s

concat + spread

9.3M/s

reduce + Array.prototype.concat

8.5M/s

Array.prototype.flat

2.6M/s

Fastest: reduce + spread (6.7x faster)

View exact numbers

✓ reduce + spread: 17,036,740 ops/sec
• concat + spread: 9,252,096 ops/sec
• reduce + Array.prototype.concat: 8,499,312 ops/sec
• Array.prototype.flat: 2,550,766 ops/sec

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

Test case name	Result
reduce + Array.prototype.concat
Array.prototype.flat
concat + spread
reduce + spread

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Mobile Safari/537.36 EdgA/142.0.0.0

Browser/OS: Chrome Mobile 142 on Android

View result in a separate tab

reduce + spread

12.0M/s

concat + spread

6.4M/s

reduce + Array.prototype.concat

6.0M/s

Array.prototype.flat

3.4M/s

View exact numbers

Test name	Executions per second
✓ reduce + spread	11,974,121 Ops/sec
concat + spread	6,375,704 Ops/sec
reduce + Array.prototype.concat	5,964,734 Ops/sec
Array.prototype.flat	3,442,352 Ops/sec

reduce.concat() vs flat() vs concat + spread vs reduce + spread (version: 0) Benchmark.js

Compare the new ES6 spread operator with the traditional concat() method

Comparing performance of: `reduce + Array.prototype.concat vs Array.prototype.flat vs concat + spread vs reduce + spread`

Created: 2 years ago by: Guest

Go to the latest result

reduce + Array.prototype.concat

Array.prototype.flat

concat + spread

reduce + spread

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

reduce.concat() vs flat() vs concat + spread vs reduce + spread (version: 0) Benchmark.js

Compare the new ES6 spread operator with the traditional concat() method

Comparing performance of: reduce + Array.prototype.concat vs Array.prototype.flat vs concat + spread vs reduce + spread

Created: 2 years ago by: Guest

Go to the latest result

reduce + Array.prototype.concat

Array.prototype.flat

concat + spread

reduce + spread

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Related benchmarks

Comparing performance of: `reduce + Array.prototype.concat vs Array.prototype.flat vs concat + spread vs reduce + spread`