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

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:140.0) Gecko/20100101 Firefox/140.0

Browser: Firefox 140

Operating system: Linux

Device Platform: Desktop

Date tested: 7 months ago

Test name	Executions per second
Using the spread operator	4453011.5 Ops/sec
Using Object.assign	6954302.5 Ops/sec
Manually copying properties	25480756.0 Ops/sec
Create new object while copying	176756176.0 Ops/sec
Create new object from scratch	175854336.0 Ops/sec
StructuredClone	244361.5 Ops/sec
JSON	397799.1 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