Benchmark: Number.parseFloat vs parseFloat

Tests:

parseFloat
let parse = parseFloat(Math.random().toString());
Number.parseFloat
let parse = Number.parseFloat(Math.random().toString());

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
parseFloat
Number.parseFloat

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:149.0) Gecko/20100101 Firefox/149.0

Browser/OS: Firefox 149 on Linux

View result in a separate tab

Test name	Executions per second
parseFloat	3821054.2 Ops/sec
Number.parseFloat	4578559.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in this JavaScript microbenchmark.

**Benchmark Goal:**
The benchmark aims to compare the performance of two functions: `parseFloat` and `Number.parseFloat`. Both functions are used to convert a string representation of a number to a floating-point number.

**Options Compared:**

1. **`parseFloat`**: This is the traditional function for parsing strings as floats. It's a built-in JavaScript method that attempts to parse a string as a float, returning NaN (Not a Number) if it can't.
2. **`Number.parseFloat`**: This is a newer addition to the JavaScript language, introduced in ECMAScript 2019. It's similar to `parseFloat`, but with some key differences:
	* It returns a `Promise` that resolves to the parsed float value, or rejects if parsing fails.
	* It can parse strings in multiple formats (e.g., "123", "-456.789", etc.) without requiring explicit parsing functions.

**Pros and Cons:**

1. **`parseFloat`**:
	* Pros: Widely supported across browsers, easy to use, and familiar to many developers.
	* Cons: Can be slower than `Number.parseFloat`, especially for large strings or complex parses.
2. **`Number.parseFloat`**:
	* Pros: Offers a safer, more robust parsing experience with better error handling and support for multiple formats.
	* Cons: Requires modern browsers that support it ( Firefox 94+), has additional overhead due to the `Promise` wrapping.

**Library Usage:**
Neither of these functions uses a library. They are built-in JavaScript methods implemented by the browser engines.

**Special JS Feature or Syntax:**
There's no special JS feature or syntax being tested here. The benchmark only focuses on the performance comparison between two existing parsing methods.

**Other Alternatives:**

If you need to parse strings as floats in older browsers that don't support `Number.parseFloat`, you can use:

1. **`Intl.NumberFormat`.formatToParts()`**: This method provides a more robust way to parse and format numbers, but it's also browser-dependent.
2. **`regular expressions`**: You can use regular expressions to parse strings as floats, but this approach requires more expertise and can be slower.

Overall, the benchmark helps determine which parsing method is faster and more efficient for common use cases, especially when using modern browsers that support `Number.parseFloat`.

Related benchmarks:

Number.parseFloat vs parseFloat (version: 0)

Comparing performance of: parseFloat vs Number.parseFloat

Created: 4 years ago by: Guest

Jump to the latest result

parseFloat

Number.parseFloat

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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