Benchmark: JSON.parse vs fast-json-parse

Script Preparation code:

var valid = ['false', 'true', '2.5', '{"test": 1}'];
var invalid = ['025', 'text', 'FALSE', 'TRUE', '{cat}'];
var combined = [...valid, ...invalid];

// src from https://www.npmjs.com/package/fast-json-parse
function Parse (data) {
  if (!(this instanceof Parse)) {
    return new Parse(data)
  }
  this.err = null
  this.value = null
  try {
    this.value = JSON.parse(data)
  } catch (err) {
    this.err = err
  }
}

var fastJsonParse = Parse;

Tests:

JSON.parse combined
combined.map((value) => { try { return JSON.parse(value); } catch(e) { return null; } })
JSON.parse invalid
invalid.map((value) => { try { return JSON.parse(value); } catch(e) { return null; } })
JSON.parse valid
valid.map((value) => { try { return JSON.parse(value); } catch(e) { return null; } })
fast-json-parse combined
combined.map((value) => { const result = fastJsonParse(value); return result.err ? null : result.value; })
fast-json-parse invalid
invalid.map((value) => { const result = fastJsonParse(value); return result.err ? null : result.value; })
fast-json-parse valid
valid.map((value) => { const result = fastJsonParse(value); return result.err ? null : result.value; })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
JSON.parse combined
JSON.parse invalid
JSON.parse valid
fast-json-parse combined
fast-json-parse invalid
fast-json-parse valid

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 4 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.127 Safari/537.36 OPR/60.3.3004.55692

Browser/OS: Opera 60 on Linux

View result in a separate tab

Test name	Executions per second
JSON.parse combined	3553.4 Ops/sec
JSON.parse invalid	3950.8 Ops/sec
JSON.parse valid	70621.8 Ops/sec
fast-json-parse combined	2928.5 Ops/sec
fast-json-parse invalid	3131.4 Ops/sec
fast-json-parse valid	50195.5 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The benchmark is designed to compare the performance of two approaches: `JSON.parse` and `fast-json-parse`. The test harness creates an array of valid and invalid JSON strings, which are then processed using both methods.

**JSON.parse vs fast-json-parse**

**JSON.parse**

* This method parses a JSON string into a JavaScript object.
* It throws an error if the input string is not a valid JSON.
* It uses the built-in `JSON.parse` function in the browser's JavaScript engine.
* The performance of this method depends on the browser's implementation and the complexity of the input data.

**fast-json-parse**

* This is a custom parsing library, written in JavaScript, which implements a optimized JSON parsing algorithm.
* It throws an error if the input string is not a valid JSON.
* It uses a different parsing approach than `JSON.parse`, which can lead to performance differences.

**Comparison and Pros/Cons**

The benchmark compares the performance of both methods on various test cases. The results show that:

* `fast-json-parse` is generally faster than `JSON.parse` for most test cases.
* However, `JSON.parse` may perform better for very large input data or complex JSON structures.
* Both methods have their own strengths and weaknesses, and the choice of which one to use depends on the specific requirements of the application.

**Other Considerations**

* **Error handling**: Both methods throw an error if the input string is not a valid JSON. However, `fast-json-parse` may handle errors more efficiently than `JSON.parse`.
* **Memory usage**: The memory usage of both methods can vary depending on the size and complexity of the input data.

**Library: fast-json-parse**

The `fast-json-parse` library is a custom implementation of a JSON parsing algorithm. It uses a optimized approach to parse JSON strings, which can lead to better performance compared to the built-in `JSON.parse` function.

**Special JS Features/ Syntax**

There are no special JavaScript features or syntax used in this benchmark. The focus is on comparing the performance of two different approaches to parsing JSON strings.

**Alternatives**

Other alternatives for parsing JSON strings include:

* Using a dedicated library like `json-stringify-safe` or `json-stringify`
* Implementing a custom parsing algorithm using a language like C++ or Rust
* Using a WebAssembly-based approach, which can provide better performance and security compared to traditional JavaScript parsing.

However, these alternatives may have their own trade-offs in terms of complexity, performance, and compatibility with different browsers and platforms.

Related benchmarks:

JSON.parse vs fast-json-parse (version: 0)

Comparing performance of: JSON.parse combined vs JSON.parse invalid vs JSON.parse valid vs fast-json-parse combined vs fast-json-parse invalid vs fast-json-parse valid

Created: 4 years ago by: Guest

Jump to the latest result

JSON.parse combined

JSON.parse invalid

JSON.parse valid

fast-json-parse combined

fast-json-parse invalid

fast-json-parse valid

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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