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

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser: Chrome 132

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
Using the spread operator	68717960.0 Ops/sec
Using Object.assign	16293537.0 Ops/sec
Manually copying properties	84453096.0 Ops/sec
Create new object while copying	213102496.0 Ops/sec
Create new object from scratch	208646528.0 Ops/sec
StructuredClone	792174.0 Ops/sec
JSON	2724264.2 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