Run results for: findIndex vs indexOf - JavaScript performance with objects

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:138.0) Gecko/20100101 Firefox/138.0

Browser: Firefox 138

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

indexOf

6.7M/s

findIndex

82K/s

View exact numbers

Test name	Executions per second
✓ indexOf	6,748,704 Ops/sec
findIndex	81,932 Ops/sec

Script Preparation code:

let arr = new Array(15000);
arr.fill({
    id: 0,
    stuff: "stuff"
});
arr = arr.map((el, idx) => ({
    ...el,
    id: idx
}));
let foo = arr.find((el) => el.id === Math.floor(Math.random() * 15000));

Tests:

findIndex
let index = arr.findIndex((el) => el === foo);
indexOf
let index = arr.indexOf(foo);