Benchmark: +string vs Number vs parseInt

Script Preparation code:

var string = '15.75'

Tests:

+string
let num = +string
Number
let num = Number(string)
parseInt
let num = parseInt(string)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
+string
Number
parseInt

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser/OS: Chrome 122 on Windows

View result in a separate tab

Test name	Executions per second
+string	22370128.0 Ops/sec
Number	22473378.0 Ops/sec
parseInt	28228484.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to help explain the benchmark and its test cases.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmarking experiment, specifically designed to compare the performance of three methods for parsing or converting string values into numerical values: `+string`, `Number(string)`, and `parseInt(string)`.

**Test Case Options**

The three test cases are designed to evaluate the performance of each option:

1. **`+string`**: This method uses the unary plus operator (`+`) to convert the string value to a number. It's equivalent to calling `Number(string)`.
2. **`Number(string)``**: This method calls the built-in `Number()` function to convert the string value to a number.
3. **`parseInt(string)`**: This method uses the `parseInt()` function with no radix argument (defaulting to 10) to convert the string value to an integer.

**Pros and Cons of Each Approach**

Here's a brief summary of each approach:

*   **`+string` and `Number(string)`**: Both methods are simple and straightforward. They're also relatively fast, as they don't involve any additional function calls or overhead.
    *   Pros: Fast, easy to implement, and widely supported in JavaScript engines.
    *   Cons: May incur a small performance penalty due to the unnecessary conversion from string to number (though this is usually negligible).
*   **`parseInt(string)`**: This method can be slower than the other two options because it involves an additional function call and may require more overhead, especially if the radix argument needs to be explicitly specified.
    *   Pros: Can provide better results when working with specific numerical formats or requiring explicit control over parsing.
    *   Cons: May be slower due to the added function call and potential performance overhead.

**Library Usage**

There is no library used in this benchmarking experiment. The test cases rely solely on built-in JavaScript features (`+`, `Number()`, and `parseInt()`).

**Special JS Features or Syntax (None)**

This benchmark doesn't utilize any special JavaScript features or syntax beyond the basic conversion methods mentioned above.

**Other Alternatives**

While not explicitly tested, other alternatives to these methods might include:

*   Using a library like `numeral.js` or `moment.js`, which provide more advanced string-to-number parsing capabilities.
*   Utilizing Web APIs like `Internationalization API` for handling numerical formats and locale-specific conversions.
*   Leveraging specialized libraries like `parse` from the `punycode` package, which is used for URL decoding and parsing.

Keep in mind that these alternatives might not be relevant to this specific benchmarking experiment, as it focuses on basic string-to-number conversion performance.

Related benchmarks:

+string vs Number vs parseInt (version: 0)

Comparing performance of: +string vs Number vs parseInt

Created: 4 years ago by: Registered User

Jump to the latest result

+string

Number

parseInt

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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