Benchmark: JSON.stringify vs structuredClone 3

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...'
  }
};

var myCopy = null;

Tests:

JSON.stringify
var obj = { [Math.random(2000).toString()]: Math.random(2000).toString(), ...MyObject, [Math.random(2000).toString()]: Math.random(2000).toString(), }; myCopy = JSON.parse(JSON.stringify(obj));
structuredClone
var obj = { [Math.random(2000).toString()]: Math.random(2000).toString(), ...MyObject, [Math.random(2000).toString()]: Math.random(2000).toString(), }; myCopy = structuredClone(obj);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
JSON.stringify
structuredClone

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36

Browser/OS: Chrome 143 on Linux

View result in a separate tab

Test name	Executions per second
JSON.stringify	310627.7 Ops/sec
structuredClone	242371.4 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's being tested.

**Benchmark Overview**

The benchmark compares the performance of `JSON.stringify()` and `structuredClone()` in creating a deep copy of an object. The object has some randomly generated properties, including arrays and a nested object with a string value.

**Options Compared**

Two options are compared:

1. **`JSON.stringify()`**: This method converts a JavaScript value to a JSON string, which is then parsed back into a JavaScript object using `JSON.parse()`. The resulting object is not a deep copy of the original.
2. **`structuredClone()`**: This is a relatively new function introduced in JavaScript 2020 (ECMAScript 2020) as part of the WebAssembly feature. It creates a deep clone of an object, including arrays and nested objects.

**Pros and Cons**

**`JSON.stringify()`**:

Pros:

* Widely supported and well-established.
* Can be used to serialize data for storage or transmission.

Cons:

* Not a deep copy, as it only serializes the object's values, not its references. This can lead to unexpected behavior when modifying the copied object.
* Can be slower than `structuredClone()` due to the additional parsing step.

**`structuredClone()`**:

Pros:

* Creates a true deep copy of the object, including arrays and nested objects.
* Optimized for performance compared to `JSON.stringify()`.
* Newer and more modern function.

Cons:

* Less widely supported (only available in JavaScript 2020+).
* Requires special consideration when working with older browsers or environments.

**Library and Special JS Feature**

In this benchmark, no specific library is used. However, note that the use of `structuredClone()` relies on a relatively new JavaScript feature.

**Test Case Analysis**

The two test cases are identical, but they differ in the implementation:

1. **`JSON.stringify()`**: This test case uses the `JSON.stringify()` method to create a copy of the object.
2. **`structuredClone()`**: This test case uses the `structuredClone()` function to create a deep clone of the object.

Both tests aim to measure the performance difference between these two approaches.

**Other Alternatives**

If you need an alternative for creating deep copies, consider using:

1. **Lodash's `cloneDeep()` method**: A popular library that provides a safe and efficient way to create deep clones.
2. **Underscore.js's `_cloneDeep()` function**: Another widely used library that offers similar functionality.

These alternatives can provide more flexibility and control over the cloning process, but they may introduce additional dependencies or complexity.

Related benchmarks:

JSON.stringify vs structuredClone 3 (version: 0)

JSON.stringify vs structuredClone

Comparing performance of: JSON.stringify vs structuredClone

Created: 3 years ago by: Guest

Jump to the latest result

JSON.stringify

structuredClone

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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