Benchmark: Number vs parseFloat

Tests:

number test
Number('2.4')
parse test
parseFloat('2.4')

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
number test
parse test

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (X11; Fedora; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.93 Safari/537.36

Browser/OS: Chrome 96 on Fedora

View result in a separate tab

Test name	Executions per second
number test	5001894.5 Ops/sec
parse test	3236354.2 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested.

**What is tested:**
The benchmark measures the performance difference between using `Number()` and `parseFloat()` to convert a string to a number in JavaScript.

**Options compared:**

1. **`Number()`**: This function attempts to parse the string as an integer. If the conversion fails, it returns 0.
2. **`parseFloat()`**: This function attempts to parse the string as a floating-point number. If the conversion fails, it returns NaN (Not a Number).

**Pros and cons of each approach:**

* `Number()`:
	+ Pros:
		- Generally faster since it doesn't need to handle decimal points.
		- Can be more suitable for certain use cases where an integer value is expected.
	+ Cons:
		- Will return 0 if the conversion fails, which might not be the desired behavior.
		- May not handle negative numbers correctly (in older browsers).
* `parseFloat()`:
	+ Pros:
		- Returns NaN if the conversion fails, making it a better choice for situations where an exact number is expected.
		- Handles decimal points and negative numbers more accurately than `Number()`.
	+ Cons:
		- Generally slower since it needs to handle decimal points.
		- May be overkill for simple integer conversions.

**Library usage:**
None of the provided benchmark scripts use any external libraries. The focus is solely on comparing the performance of `Number()` and `parseFloat()` within JavaScript itself.

**Special JS features or syntax:**
There are no special JS features or syntax used in this benchmark beyond what's standard for basic arithmetic operations.

**Other alternatives:**

1. **`parseInt()`**: This function is similar to `Number()`, but it allows specifying a radix (base) for parsing strings. For example, `parseInt('123', 10)` would parse '123' as an integer base-10.
2. **`toFloat32Array()` and `toFloat64Array()`**: These functions create a typed array with floating-point values. You could potentially use these to compare performance with `parseFloat()`, but it's not directly related to the `Number()` vs `parseFloat()` comparison.

For those new to JavaScript, here's a brief overview of how these functions work:

* `Number()` and `parseInt()` convert strings to numbers based on their value.
* `parseFloat()` attempts to parse strings as floating-point numbers.
* `toFloat32Array()` and `toFloat64Array()` create typed arrays with specific types (float 32-bit or float 64-bit) for numerical data.

When working with performance-critical code, understanding these differences can help you optimize your JavaScript applications effectively.

Related benchmarks:

Number vs parseFloat (version: 0)

Comparing performance of: number test vs parse test

Created: 3 years ago by: Guest

Jump to the latest result

number test

parse test

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):