Run results for: JS Variable Performance (const vs let vs var)

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 18_7 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/26.0.1 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 26

Operating system: iOS 18.7

Device Platform: Mobile

Date tested: 11 months ago

Benchmark engine: Benchmark.js

TEST_1: VAR

40.1M/s

TEST_2: LET

37.8M/s

TEST_3: CONST

35.5M/s

View exact numbers

Test name	Executions per second
✓ TEST_1: VAR	40,114,956 Ops/sec
TEST_2: LET	37,794,804 Ops/sec
TEST_3: CONST	35,478,096 Ops/sec

HTML Preparation code:

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

Script Preparation code:

/*your preparation JavaScript code goes here
To execute async code during the script preparation, wrap it as function globalMeasureThatScriptPrepareFunction, example:*/
async function globalMeasureThatScriptPrepareFunction() {
    // This function is optional, feel free to remove it.
    // await someThing();
}

Tests:

TEST_1: VAR
var g = { e: [] } g.o = function(x) { g.e.push(...[1,2,3]) } g.o()
TEST_2: LET
let g = { e: [] } g.o = function(x) { g.e.push(...[1,2,3]) } g.o()
TEST_3: CONST
const g = { e: [] } g.o = function(x) { g.e.push(...[1,2,3]) } g.o()