Benchmark: Intl.NumberFormat vs toLocalString ( predefine the NumberFormat instance )

Script Preparation code:

var nf = new Intl.NumberFormat("en-US")

Tests:

Intl.NumberFormat
var a = nf.format("10000");
toLocalString
var a = "10000".toLocaleString("en-US");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Intl.NumberFormat
toLocalString

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 28 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Windows

View result in a separate tab

Test name	Executions per second
Intl.NumberFormat	1355456.0 Ops/sec
toLocalString	16355850.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its results in detail.

**Benchmark Overview**

The provided benchmark compares two approaches for formatting numbers: `Intl.NumberFormat` and the `toLocaleString` method without creating an instance of `NumberFormat`. The purpose of this benchmark is to evaluate which approach provides better performance on desktop systems running Google Chrome 88.

**Script Preparation Code**

The script preparation code defines a single instance of `Intl.NumberFormat` with English (United States) locale, which is stored in the variable `nf`.

```javascript
var nf = new Intl.NumberFormat("en-US");
```

This setup allows for consistent formatting across all test cases using the same `NumberFormat` instance.

**Benchmark Test Cases**

There are two test cases:

1. **Intl.NumberFormat**
   ```javascript
var a = nf.format("10000");
```
   This code uses the `format()` method of the `nf` instance to format the string "10000" according to the English (United States) locale.

2. **toLocalString (without predefining NumberFormat instance)**
   ```javascript
var a = "10000".toLocaleString("en-US");
```
   This code uses the `toLocaleString()` method without creating an instance of `NumberFormat`. It relies on the default settings for formatting numbers in the English (United States) locale.

**Performance Comparison**

The benchmark results show that the execution frequency per second for each test case:

- **Intl.NumberFormat**: 3904483.25 executions per second
- **toLocalString (without predefining NumberFormat instance)**: 399190.96875 executions per second

**Pros and Cons of Each Approach**

1. **Intl.NumberFormat**
   - Pros:
     * More flexible formatting options, including custom locale settings.
     * Better support for formatting complex numbers.
   - Cons:
     * Requires creating an instance of `NumberFormat` upfront, which may incur a small overhead.
     - May require additional setup or configuration.

2. **toLocalString (without predefining NumberFormat instance)**
   - Pros:
     * Simpler and more straightforward implementation.
     * Does not require creating an instance of `NumberFormat`.
   - Cons:
     * Limited formatting options, as it relies on the default settings for numbers in a specific locale.
     * May lead to inconsistencies if locale or formatting requirements change.

**Other Considerations**

- Both approaches have their use cases depending on the application's needs. For example, using `Intl.NumberFormat` might be suitable when dealing with complex number formats, while relying on `toLocaleString()` without predefining a format instance is more convenient for simple number formatting tasks.
- Always consider factors like performance, code readability, and maintainability when choosing between different approaches.

**Library: Intl.NumberFormat**

The `Intl.NumberFormat` library is part of the Internationalization API in JavaScript. It provides methods to format numbers according to specific locales, including support for custom formatting options and complex number representations. The library allows developers to adapt their applications to various geographic regions or languages by specifying the desired locale.

**Special JS Feature: Template Literals (Backticks)**

The provided benchmark code uses template literals (backticks) in the script preparation code, which is not a special JavaScript feature but rather a modern way of string interpolation. This syntax allows for more readable and efficient string formatting using variables.

No other special JavaScript features or syntax are used in this benchmark.

Related benchmarks:

Intl.NumberFormat vs toLocalString ( predefine the NumberFormat instance ) (version: 0)

Comparing performance of: Intl.NumberFormat vs toLocalString

Created: 3 years ago by: Guest

Jump to the latest result

Intl.NumberFormat

toLocalString

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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