Benchmark: JSON.stringify vs structuredClone (with deeply nested objects)

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...'
  },
  deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {deep: {}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}
};

var myCopy = null;

Tests:

JSON.stringify
myCopy = JSON.parse(JSON.stringify(MyObject));
structuredClone
myCopy = structuredClone(MyObject);

Historical Performance Data aggregated from 35 community runs

Desktop Results:

Chrome 28 runs

JSON.stringify

167K/s

structuredClone

98K/s

Fastest: JSON.stringify (1.7x faster)

View exact numbers

✓ JSON.stringify: 167,362 ops/sec
• structuredClone: 98,467 ops/sec

Firefox 7 runs

structuredClone

103K/s

JSON.stringify

76K/s

Fastest: structuredClone (1.4x faster)

View exact numbers

✓ structuredClone: 102,952 ops/sec
• JSON.stringify: 76,146 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
JSON.stringify
structuredClone

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36

Browser/OS: Chrome 147 on Windows

View result in a separate tab

JSON.stringify

297K/s

structuredClone

114K/s

View exact numbers

Test name	Executions per second
✓ JSON.stringify	297,188 Ops/sec
structuredClone	113,860 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided benchmark compares two JavaScript methods for creating copies of objects: `JSON.stringify` and `structuredClone`. The benchmark measures which method is faster and more efficient.

**Options Compared**

Two options are compared:

1. **JSON.stringify**: This method converts a JavaScript object to a JSON string, which can be easily parsed back into an object using `JSON.parse()`.
2. **structuredClone**: This method creates a deep copy of an object without converting it to a JSON string. It is designed to work with objects that contain cyclic references (i.e., objects that reference themselves) and is considered more efficient than `JSON.stringify` for large objects.

**Pros and Cons**

* **JSON.stringify**:
	+ Pros: Simple and widely supported, can be used for serializing data.
	+ Cons: Can create a new object with different properties and methods, which may not be desirable for all use cases. Also, it converts the entire object to a JSON string, including any cyclic references, which can lead to a large amount of memory usage.
* **structuredClone**:
	+ Pros: Creates an exact copy of the original object, including all its properties and methods, without converting it to a JSON string. It is more efficient for large objects and can handle cyclic references.
	+ Cons: Less widely supported than `JSON.stringify`, may require additional dependencies or libraries.

**Library Used**

* **structuredClone**: This method is part of the ECMAScript standard since ECMAScript 2020 (ES10). However, it was not widely supported until recently. Mezzanine (https://github.com/Mezzanine-Team/mezzanine) and V8 (https://v8.dev/) are two notable implementations that have contributed to its adoption.

**Special JavaScript Feature/Syntax**

* **Cyclic References**: The benchmark creates objects with cyclic references, which is a common challenge when serializing data. `structuredClone` is designed to handle these cases efficiently.
* **Object Deep Copying**: Both methods create deep copies of the original object, but `structuredClone` does so without converting it to a JSON string.

**Other Alternatives**

If you need to compare other serialization techniques, here are some alternatives:

1. **Lodash.cloneDeep()**: A popular library that provides a deep copy function for objects.
2. **immer**: A library that provides a way to create immutable objects by creating a shallow copy and then modifying the copy.
3. **JSON.parse(JSON.stringify(object))**: While not as efficient as `structuredClone`, this method can still be used for simple object copying.

In summary, the benchmark compares two popular methods for serializing JavaScript objects: `JSON.stringify` and `structuredClone`. While `JSON.stringify` is widely supported and simple to use, it has limitations when dealing with cyclic references or large objects. `structuredClone` provides a more efficient solution but is less widely adopted.

JSON.stringify vs structuredClone (with deeply nested objects) (version: 0)

JSON.stringify vs structuredClone

Comparing performance of: `JSON.stringify vs structuredClone`

Created: 2 years ago by: Guest

Go to the latest result

JSON.stringify

structuredClone

Historical Performance Data aggregated from 35 community runs

Desktop Results:

Chrome 28 runs

Firefox 7 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

JSON.stringify vs structuredClone (with deeply nested objects) (version: 0)

JSON.stringify vs structuredClone

Comparing performance of: JSON.stringify vs structuredClone

Created: 2 years ago by: Guest

Go to the latest result

JSON.stringify

structuredClone

Historical Performance Data aggregated from 35 community runs

Desktop Results:

Chrome 28 runs

Firefox 7 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `JSON.stringify vs structuredClone`