Benchmark: for-in vs Object.keys benchmark 3

Script Preparation code:

var codes = Array.from(Array(26)).map((_, i) => i + 65);
var alphabet = codes.reduce((acc, code) => {
  acc[String.fromCharCode(code)] = code;

  return acc;
}, {});

Tests:

for-in
for (var i=1000; i > 0; i--) { var result = {}; for (var key in alphabet) { result[key] = alphabet[key]; } };
Object.keys with forEach
for (var i=1000; i > 0; i--) { var result = {}; Object.keys(alphabet).forEach(key => { result[key] = alphabet[key]; }); };
Object.keys with reduce
for (var i=1000; i > 0; i--) { var result = Object.keys(alphabet).reduce((acc, key) => { acc[key] = alphabet[key]; return acc; }, {}); };
Object.keys with for-of
for (var i=1000; i > 0; i--) { var result = {}; for (var key of Object.keys(alphabet)) { result[key] = alphabet[key]; } };
for-in with hasOwnProperty
for (var i=1000; i > 0; i--) { var result = {}; for (var key in alphabet) { if (Object.prototype.hasOwnProperty.call(alphabet, key)) { result[key] = alphabet[key]; } } };

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for-in
Object.keys with forEach
Object.keys with reduce
Object.keys with for-of
for-in with hasOwnProperty

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 5 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; rv:120.0) Gecko/20100101 Firefox/120.0

Browser/OS: Firefox 120 on Windows

View result in a separate tab

Test name	Executions per second
for-in	5101.5 Ops/sec
Object.keys with forEach	3798.3 Ops/sec
Object.keys with reduce	3967.2 Ops/sec
Object.keys with for-of	2921.3 Ops/sec
for-in with hasOwnProperty	3089.0 Ops/sec

for-in vs Object.keys benchmark 3 (version: 2)

Comparing performance of: for-in vs Object.keys with forEach vs Object.keys with reduce vs Object.keys with for-of vs for-in with hasOwnProperty

Created: 2 years ago by: Registered User

Jump to the latest result

for-in

Object.keys with forEach

Object.keys with reduce

Object.keys with for-of

for-in with hasOwnProperty

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A