Benchmark: cached Intl.NumberFormat vs new Intl.NumberFormat vs toLocaleString

Tests:

cached Intl.NumberFormat
window.a = window.a || new Intl.NumberFormat("en-US"); var a = window.a.format("10000")
new Intl.NumberFormat
var a = new Intl.NumberFormat("en-US");
toLocaleString
var a = "10000".toLocaleString("en-US");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
cached Intl.NumberFormat
new Intl.NumberFormat
toLocaleString

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

Autogenerated LLM Summary (model llama3.1:latest, generated one year ago):

LLMs can make mistakes. Check important info.

Let's dive into the details of this benchmark.

**What is being tested?**

The benchmark tests three different approaches to formatting numbers in JavaScript:

1. **Cached Intl.NumberFormat**: This approach creates an instance of `Intl.NumberFormat` and caches it globally, so that it can be reused across multiple executions.
2. **New Intl.NumberFormat**: This approach creates a new instance of `Intl.NumberFormat` on each execution.
3. **toLocaleString**: This approach uses the `toLocaleString()` method to format numbers, which is a built-in method in JavaScript.

**What options are being compared?**

The benchmark compares three different approaches:

1. Using a cached `Intl.NumberFormat` instance (approach 1)
2. Creating a new `Intl.NumberFormat` instance on each execution (approach 2)
3. Using the `toLocaleString()` method to format numbers (approach 3)

**Pros and Cons of each approach:**

1. **Cached Intl.NumberFormat**: Pros:
	* Faster execution times, as the cached instance is reused.
	* Reduced memory allocation overhead.
Cons:
	* May lead to inconsistent formatting behavior if the cached instance is not properly reset or updated.
2. **New Intl.NumberFormat**: Pros:
	* Consistent formatting behavior on each execution.
	* No risk of caching issues.
Cons:
	* Slower execution times, as a new instance is created on each execution.
3. **toLocaleString**: Pros:
	* Simple and lightweight implementation.
	* Fast execution times.
Cons:
	* May not support all the features of `Intl.NumberFormat`, such as locale-specific formatting options.

**Library used:**

None. This benchmark uses only standard JavaScript features, without any external libraries.

**Special JS feature or syntax used:**

None, apart from the use of `Intl.NumberFormat` and `toLocaleString()` methods, which are built-in in modern browsers.

**Other considerations:**

* The benchmark uses a specific locale ("en-US") to format numbers.
* The test cases execute the formatting function multiple times to measure performance.
* The results show significant differences in execution speeds between the three approaches.

**Alternatives:**

If you need more control over number formatting, consider using libraries like `numeral.js` or `moment.js`. However, for simple formatting tasks, the built-in methods and approaches tested here may be sufficient.

Related benchmarks:

cached Intl.NumberFormat vs new Intl.NumberFormat vs toLocaleString (version: 0)

Comparing performance of: cached Intl.NumberFormat vs new Intl.NumberFormat vs toLocaleString

Created: 5 years ago by: Guest

Jump to the latest result

cached Intl.NumberFormat

new Intl.NumberFormat

toLocaleString

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.1:latest, generated one year ago):