Benchmark: json stringify vs array tostring vs array join

Script Preparation code:

function moreData(arr, left) {
  if(left === 0) return arr;
  else {
    arr.push(Math.floor(Math.random() * 256));
  	return moreData(arr, left - 1);
  }
}
function makeTestData() { return moreData([], 4); }

Tests:

toString
makeTestData().toString()
JSON.stringify
JSON.stringify(makeTestData());
Array.join
makeTestData().join(',')

Historical Performance Data aggregated from 25 community runs

Desktop Results:

Chrome 18 runs

Array.join

1.3M/s

toString

1.2M/s

JSON.stringify

1.2M/s

View exact numbers

✓ Array.join: 1,254,685 ops/sec
• toString: 1,205,235 ops/sec
• JSON.stringify: 1,172,894 ops/sec

Firefox 7 runs

toString

4.7M/s

Array.join

2.5M/s

JSON.stringify

2.1M/s

Fastest: toString (2.3x faster)

View exact numbers

✓ toString: 4,675,918 ops/sec
• Array.join: 2,544,673 ops/sec
• JSON.stringify: 2,070,488 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
toString
JSON.stringify
Array.join

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:152.0) Gecko/20100101 Firefox/152.0

Browser/OS: Firefox 152 on Windows

View result in a separate tab

Array.join

2.7M/s

toString

2.3M/s

JSON.stringify

1.1M/s

View exact numbers

Test name	Executions per second
✓ Array.join	2,724,909 Ops/sec
toString	2,254,464 Ops/sec
JSON.stringify	1,079,823 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 its test cases.

**Benchmark Purpose**

The benchmark compares three ways to convert an array of numbers into a string:

1. `toString()`: The built-in `toString()` method is called on the array, which converts it to a string representation.
2. `JSON.stringify()`: The `JSON.stringify()` function is used to convert the array to a JSON string.
3. `Array.join(',')`: The `join()` method of the array is used with a comma (`','`) separator to concatenate the elements into a single string.

**Options Compared**

The benchmark compares the performance of these three approaches on an array of 4 randomly generated numbers, created using the `makeTestData()` function.

**Pros and Cons of Each Approach:**

1. `toString()`:
	* Pros: Simple, widely supported, and efficient.
	* Cons: May not produce a human-readable string representation, and can be slower for large arrays due to the overhead of concatenation.
2. `JSON.stringify()`:
	* Pros: Produces a JSON string that is easy to parse and understand, and is often used in serialization scenarios.
	* Cons: Can be slower than `toString()` due to the overhead of parsing and generating the JSON string, and may not be suitable for all use cases (e.g., security-sensitive data).
3. `Array.join(',')`:
	* Pros: Fast and efficient, producing a human-readable string representation.
	* Cons: May require more memory for large arrays, and can be slower than `toString()` if the separator is not optimized.

**Library Usage**

The benchmark uses the `JSON` object from the JavaScript standard library to implement `JSON.stringify()`. The `join()` method is also part of the standard library. No external libraries are required.

**Special JS Features/Syntax**

None mentioned in this specific benchmark, but it's worth noting that some features like `async/await`, `let const`, and `template literals` may be used in the `makeTestData()` function, but their presence is not relevant to the comparison of these three string conversion methods.

**Alternatives**

Other alternatives for converting an array to a string include:

* Using a library like Lodash or underscore.js
* Implementing a custom loop that concatenates the elements
* Using a streaming-based approach (e.g., using a `ReadableStream` and `Stringstream`)
* Using a more advanced data structure like a `Buffer`

In general, the choice of string conversion method depends on the specific use case, performance requirements, and personal preference.

json stringify vs array tostring vs array join (version: 0)

Comparing performance of: `toString vs JSON.stringify vs Array.join`

Created: 5 years ago by: Guest

Go to the latest result

toString

JSON.stringify

Array.join

Historical Performance Data aggregated from 25 community runs

Desktop Results:

Chrome 18 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 array tostring vs array join (version: 0)

Comparing performance of: toString vs JSON.stringify vs Array.join

Created: 5 years ago by: Guest

Go to the latest result

toString

JSON.stringify

Array.join

Historical Performance Data aggregated from 25 community runs

Desktop Results:

Chrome 18 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: `toString vs JSON.stringify vs Array.join`