Benchmark: substring vs. slice vs. replace to remove string from end of input string

substring vs. slice vs. replace to remove string from end of input string (version: 3)

Determine the fastest way to remove a string from the end of another string.

Comparing performance of: Using String.replace() vs Using String.substring() with a lastIndexOf() search vs Using String.substring() with a magic number vs Using String.slice() vs Using String.slice() without a pre-calculated suffix length

Created: 9 months ago by: Registered User

Jump to the latest result

Script Preparation code:

var numOfStrings = 100000
var suffix = 'TestStringHere'
var suffixLength = suffix.length
var negSuffixLength = suffixLength * -1
var testStrings = []

// Generate test string as a UUID + the suffix above.
function uuidv4() {
   return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g,
   function(c) {
      var uuid = Math.random() * 16 | 0, v = c == 'x' ? uuid : (uuid & 0x3 | 0x8);
      return uuid.toString(16);
   });
}

for (let i = 0; i < numOfStrings; i++) {
  testStrings.push(uuidv4() + suffix)
}

Tests:

Using String.replace()
testStrings.map(str => { return str.replace(suffix, '') })
Using String.substring() with a lastIndexOf() search
testStrings.map(str => { return str.substring(0, str.lastIndexOf(suffix)) })
Using String.substring() with a magic number
testStrings.map(str => { return str.substring(0, str.length - suffixLength) })
Using String.slice()
testStrings.map(str => { return str.slice(0, negSuffixLength) })
Using String.slice() without a pre-calculated suffix length
testStrings.map(str => { return str.slice(0, suffix.length * -1) })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using String.replace()
Using String.substring() with a lastIndexOf() search
Using String.substring() with a magic number
Using String.slice()
Using String.slice() without a pre-calculated suffix length

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser/OS: Chrome 114 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Using String.replace()	136.6 Ops/sec
Using String.substring() with a lastIndexOf() search	147.4 Ops/sec
Using String.substring() with a magic number	193.6 Ops/sec
Using String.slice()	195.7 Ops/sec
Using String.slice() without a pre-calculated suffix length	187.7 Ops/sec

substring vs. slice vs. replace to remove string from end of input string (version: 3)

Determine the fastest way to remove a string from the end of another string.

Comparing performance of: Using String.replace() vs Using String.substring() with a lastIndexOf() search vs Using String.substring() with a magic number vs Using String.slice() vs Using String.slice() without a pre-calculated suffix length

Created: 9 months ago by: Registered User

Jump to the latest result

Using String.replace()

Using String.substring() with a lastIndexOf() search

Using String.substring() with a magic number

Using String.slice()

Using String.slice() without a pre-calculated suffix length

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A