Benchmark: testing different solutions with objects in reduce

HTML Preparation code:

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

Script Preparation code:

let data = [];

for (let i = 0; i < 1000; i++) {
	data.push(i);
}

let obj = data.reduce((acc, item) => ({ ...acc, id: item }), {});

Tests:

spread
let newObj = Object.keys(obj).reduce((acc, key) => ({ ...acc, [key]: obj[key] + 1 }), {})
new prop in acc
let newObj = Object.keys(obj).reduce((acc, key) => { acc[key] = obj[key] + 1; return acc; }, {});
new prop by object assign
let newObj = Object.keys(obj).reduce((acc, key) => Object.assign(acc, { [key]: obj[key] + 1 }), {})
just new acc without enumeration
let newObj = Object.keys(obj).reduce((acc, key) => ({ result: acc.result + obj[key]}),{ result: 0 })
just old acc without enumeration
let newObj = Object.keys(obj).reduce((acc, key) => { acc.result += obj[key]; return acc; }, { result: 0 });

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Chrome 5 runs

new prop in acc

72.8M/s

spread

44.6M/s

Fastest: new prop in acc (1.6x faster)

View exact numbers

✓ new prop in acc: 72,780,560 ops/sec
• spread: 44,576,928 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
spread
new prop in acc
new prop by object assign
just new acc without enumeration
just old acc without enumeration

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Safari/537.36

Browser/OS: Chrome 140 on Mac OS X 10.15.7

View result in a separate tab

just old acc without enumeration

84.9M/s

just new acc without enumeration

78.3M/s

new prop in acc

76.2M/s

spread

45.1M/s

new prop by object assign

34.3M/s

View exact numbers

Test name	Executions per second
✓ just old acc without enumeration	84,941,280 Ops/sec
just new acc without enumeration	78,269,824 Ops/sec
new prop in acc	76,229,672 Ops/sec
spread	45,143,272 Ops/sec
new prop by object assign	34,335,056 Ops/sec

testing different solutions with objects in reduce (version: 3)

Comparing performance of: `spread vs new prop in acc vs new prop by object assign vs just new acc without enumeration vs just old acc without enumeration`

Created: 10 months ago by: Registered User

Go to the latest result

spread

new prop in acc

new prop by object assign

just new acc without enumeration

just old acc without enumeration

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

testing different solutions with objects in reduce (version: 3)

Comparing performance of: spread vs new prop in acc vs new prop by object assign vs just new acc without enumeration vs just old acc without enumeration

Created: 10 months ago by: Registered User

Go to the latest result

spread

new prop in acc

new prop by object assign

just new acc without enumeration

just old acc without enumeration

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

Comparing performance of: `spread vs new prop in acc vs new prop by object assign vs just new acc without enumeration vs just old acc without enumeration`