Run results for: JSON.stringify vs structuredClone (with deeply nested objects)

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/137.0.0.0 Safari/537.36

Browser: Chrome 137

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

JSON.stringify

86K/s

structuredClone

39K/s

View exact numbers

Test name	Executions per second
✓ JSON.stringify	85,670 Ops/sec
structuredClone	39,391 Ops/sec

Script Preparation code:

var MyObject = {
  description: 'Creates a deep copy of source, which should be an object or an array.',
  myNumber: 123456789,
  myBoolean: true,
  jayson: {
    stringify: 'JSON.stringify() method converts a JavaScript value to a JSON string....',
    parse: 'JSON.parse() method parses a JSON string...'
  },
  deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
};

var myCopy = null;

Tests:

JSON.stringify
myCopy = JSON.parse(JSON.stringify(MyObject));
structuredClone
myCopy = structuredClone(MyObject);