Run results for: JavaScript fastest way to clone an object including JSON.parse and structuredClone methods

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:145.0) Gecko/20100101 Firefox/145.0

Browser: Firefox 145

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 5 months ago

Test name	Executions per second
Using the spread operator	8425241.0 Ops/sec
Using Object.assign	19193964.0 Ops/sec
Manually copying properties	47085500.0 Ops/sec
Create new object while copying	294403840.0 Ops/sec
Create new object from scratch	287935616.0 Ops/sec
StructuredClone	738484.6 Ops/sec
JSON	980034.7 Ops/sec

Tests:

Using the spread operator
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; const finalObject = {...firstObject};
Using Object.assign
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; const finalObject = Object.assign({}, firstObject);
Manually copying properties
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; let finalObject = {}; finalObject.prop0 = firstObject.prop0; finalObject.prop1 = firstObject.prop1; finalObject.prop2 = firstObject.prop2; finalObject.prop3 = firstObject.prop3; finalObject.prop4 = firstObject.prop4; finalObject.prop5 = firstObject.prop5;
Create new object while copying
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; const finalObject = { prop0: firstObject.prop0, prop1: firstObject.prop1, prop2: firstObject.prop2, prop3: firstObject.prop3, prop4: firstObject.prop4, prop5: firstObject.prop5 };
Create new object from scratch
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; const finalObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 };
StructuredClone
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; const finalObject = structuredClone(firstObject);
JSON
const firstObject = { prop0: 'Hello world', prop1: 1, prop2: 2, prop3: "3", prop4: false, prop5: 0.2 }; const finalObject = JSON.parse(JSON.stringify(firstObject));

Run results for: JavaScript fastest way to clone an object including JSON.parse and structuredClone methods

Using the spread operator

Using Object.assign

Manually copying properties

Create new object while copying

Create new object from scratch

StructuredClone

JSON