Benchmark: Object.assign vs spread vs jQuery.extend

HTML Preparation code:

<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>

Tests:

Object.assign
var params = { b:"hello", c: true, d:7 }; var other = Object.assign({ a: 2 }, params);
spread operator
var params = { b:"hello", c: true, d:7 }; var other = { a: 2, ...params };
jQuery.extend
var params = { b:"hello", c: true, d:7 }; var other = $.extend({ a: 2 }, params);

Historical Performance Data aggregated from 20 community runs

Desktop Results:

Chrome 20 runs

spread operator

19.3M/s

Object.assign

9.2M/s

jQuery.extend

6.2M/s

Fastest: spread operator (3.1x faster)

View exact numbers

✓ spread operator: 19,347,084 ops/sec
• Object.assign: 9,171,998 ops/sec
• jQuery.extend: 6,179,222 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.assign
spread operator
jQuery.extend

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Windows

View result in a separate tab

Object.assign

12.9M/s

spread operator

11.0M/s

jQuery.extend

6.6M/s

View exact numbers

Test name	Executions per second
✓ Object.assign	12,940,968 Ops/sec
spread operator	10,954,809 Ops/sec
jQuery.extend	6,573,381 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and explain what is being tested.

**Benchmark Definition**

The test compares three JavaScript methods for merging objects:

1. `Object.assign()`
2. Spread operator (`...`)
3. jQuery.extend()

**Options Compared**

Each method has its own strengths and weaknesses, which we'll discuss next:

### Object.assign()

* **Pros:**
	+ Widely supported across browsers and platforms.
	+ Simple to use.
	+ Fast (average execution time).
* **Cons:**
	+ Can be slower than the spread operator in some cases.
	+ Requires compatibility with older browsers.

### Spread Operator (`...`)

* **Pros:**
	+ Fastest average execution time among the three methods.
	+ More concise and expressive syntax.
	+ Widely supported across modern browsers.
* **Cons:**
	+ Limited support for older browsers (IE 11 and below).
	+ May be slower than Object.assign() in some cases.

### jQuery.extend()

* **Pros:**
	+ Well-known and widely used library.
	+ Supports a wider range of browsers, including older versions.
	+ Can provide additional functionality beyond basic object merging.
* **Cons:**
	+ Adds extra weight to the code due to the inclusion of the entire jQuery library.
	+ May be slower than other methods.

**Library**

The test uses jQuery 3.1.1 as the reference implementation for `jQuery.extend()`. The purpose of this function is to merge two or more objects into a single object, with the source objects' properties being overwritten by their destination values.

**Special JavaScript Feature/Syntax**

None are explicitly mentioned in this benchmark.

**Other Alternatives**

In addition to these three methods, other alternatives for merging objects include:

* Using the `Object.create()` method with the `assign` property.
* Utilizing a library like Lodash or Ramda, which provide more advanced features beyond basic object merging.
* Implementing your own custom merge function.

These alternatives may offer additional performance benefits or simplify code in specific use cases, but they are not part of the standard JavaScript API and may require additional setup.

Object.assign vs spread vs jQuery.extend (version: 0) Benchmark.js

Comparing performance of: `Object.assign vs spread operator vs jQuery.extend`

Created: 8 years ago by: Guest

Go to the latest result

Object.assign

spread operator

jQuery.extend

Historical Performance Data aggregated from 20 community runs

Desktop Results:

Chrome 20 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

Object.assign vs spread vs jQuery.extend (version: 0) Benchmark.js

Comparing performance of: Object.assign vs spread operator vs jQuery.extend

Created: 8 years ago by: Guest

Go to the latest result

Object.assign

spread operator

jQuery.extend

Historical Performance Data aggregated from 20 community runs

Desktop Results:

Chrome 20 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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