Benchmark: javascript loops over string

Tests:

for-in
const items = 'abcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyz' let index = 0; for (let i in items) { index++; }
for-of
const items = 'abcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyz' let index = 0; for (let i of items) { index++; }
for
const items = 'abcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyz' let index = 0; for(let i = 0; i < items.length; ++i) { index++; }
optimized-for
const items = 'abcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyzabcdefghijklmopqrstuvwxyz' let index = 0; for(let i = items.length; i > 0; --i) { index++; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
for-in
for-of
for
optimized-for

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 12 days ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36

Browser/OS: Chrome 124 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
for-in	118605.7 Ops/sec
for-of	1531239.0 Ops/sec
for	6949163.0 Ops/sec
optimized-for	6917485.0 Ops/sec

javascript loops over string (version: 0)

Comparing performance of: for-in vs for-of vs for vs optimized-for

Created: 14 days ago by: Guest

Jump to the latest result

for-in

for-of

for

optimized-for

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A