Benchmark: Number vs + vs parseFloat

Tests:

Number
var number = Number(Math.random().toString());
Unary +
var unary = +Math.random().toString();
parseFloat
var parse = parseFloat(Math.random().toString());

Historical Performance Data aggregated from 118 community runs

Desktop Results:

Chrome 101 runs

Unary +

4.3M/s

parseFloat

3.5M/s

Number

3.5M/s

Fastest: Unary + (1.3x faster)

View exact numbers

✓ Unary +: 4,341,412 ops/sec
• parseFloat: 3,483,474 ops/sec
• Number: 3,451,161 ops/sec

Firefox 17 runs

Unary +

7.1M/s

Number

7.0M/s

parseFloat

6.8M/s

View exact numbers

✓ Unary +: 7,079,540 ops/sec
• Number: 6,991,969 ops/sec
• parseFloat: 6,776,580 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
Number
Unary +
parseFloat

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36 Edg/143.0.0.0

Browser/OS: Chrome 143 on Windows

View result in a separate tab

Unary +

7.2M/s

Number

7.1M/s

parseFloat

7.0M/s

View exact numbers

Test name	Executions per second
✓ Unary +	7,164,234 Ops/sec
Number	7,098,779 Ops/sec
parseFloat	6,985,380 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

**Benchmark Overview**

The benchmark in question tests three different ways to convert a random string representation of a number into an actual number: `Number()`, unary `+` (also known as implicit conversion), and `parseFloat()`.

**Options Compared**

Here are the options being compared:

1. **`Number()`**: This method attempts to parse the input string as a number, using a more lenient conversion process than unary `+`.
2. **Unary `+` (`implicit conversion`)**: This method uses implicit conversion to evaluate the expression, treating the input string as a numeric literal.
3. **`parseFloat()`**: This method explicitly parses the input string as a floating-point number.

**Pros and Cons of Each Approach**

1. **`Number()`**:
	* Pros: more lenient parsing, can handle non-numeric strings without throwing an error.
	* Cons: slower than unary `+` and `parseFloat()`, may produce inaccurate results for certain input values.
2. **Unary `+` (implicit conversion)**:
	* Pros: fast, accurate, and reliable conversion to numeric value.
	* Cons: can throw errors if the input string is not a valid number, may be less lenient than `Number()` for non-numeric strings.
3. **`parseFloat()`**:
	* Pros: more explicit parsing, can handle non-numeric strings without throwing an error, and produces accurate results.
	* Cons: slower than unary `+`, may require manual input validation.

**Library and Special JS Features**

None of the benchmark test cases explicitly use any libraries or special JavaScript features beyond what's built-in to the language. However, it's worth noting that the `Number()` method uses a more lenient parsing approach, which might be affected by the presence of certain non-numeric characters in the input string.

**Other Considerations**

* **Caching**: The benchmark may use caching mechanisms (not explicitly shown) to store and reuse results for repeated runs.
* **Variance in Results**: The benchmark's execution times may vary depending on factors like system load, network conditions, or specific hardware configurations.

**Alternative Approaches**

If you wanted to explore alternative approaches, here are some options:

1. **`BigInt()`**: For very large numbers, using `BigInt()` instead of `Number()` might provide more accurate results and better performance.
2. **Regex-based parsing**: Implementing custom regex patterns for each conversion method could potentially offer improved accuracy or flexibility.
3. **Custom parsers**: Creating custom parsers for specific number formats (e.g., scientific notation) might be necessary in certain scenarios.

Keep in mind that these alternatives would likely introduce additional complexity and may not provide significant performance benefits unless carefully optimized.

Number vs + vs parseFloat (version: 0)

Comparing performance of: `Number vs Unary + vs parseFloat`

Created: 9 years ago by: Guest

Go to the latest result

Number

Unary +

parseFloat

Historical Performance Data aggregated from 118 community runs

Desktop Results:

Chrome 101 runs

Firefox 17 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Number vs + vs parseFloat (version: 0)

Comparing performance of: Number vs Unary + vs parseFloat

Created: 9 years ago by: Guest

Go to the latest result

Number

Unary +

parseFloat

Historical Performance Data aggregated from 118 community runs

Desktop Results:

Chrome 101 runs

Firefox 17 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: `Number vs Unary + vs parseFloat`