Run results for: Shallow copy vs structuredClone

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:135.0) Gecko/20100101 Firefox/135.0

Browser: Firefox 135

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

Shallow copy

8.4M/s

structuredClone

414K/s

View exact numbers

Test name	Executions per second
✓ Shallow copy	8,366,438 Ops/sec
structuredClone	414,438 Ops/sec

Script Preparation code:

var MyObject = {
  string: 'string',
  number: 123456789,
  boolean: true,
  obj: {
    stringify: 'string',
    number: '123456789'
  }
};
var copied = undefined;

Tests:

Shallow copy
copied = { ...MyObject }
structuredClone
copied = structuredClone(MyObject)