Benchmark: parseInt vs toString

Script Preparation code:

var intA = 42.034;
var strB = "42.034";

Tests:

toString
var res = intA.toString()
parseInt
var res = parseInt(strB);
Number
var res = Number(strB);
String
var res = String(intA);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
toString
parseInt
Number
String

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Windows

View result in a separate tab

Test name	Executions per second
toString	99424824.0 Ops/sec
parseInt	189673936.0 Ops/sec
Number	174174064.0 Ops/sec
String	94253256.0 Ops/sec

Autogenerated LLM Summary (model gpt-4o-mini, generated 5 days ago):

LLMs can make mistakes. Check important info.

This benchmark compares several methods for converting values between number and string types in JavaScript. It evaluates the performance of different approaches for achieving this—specifically `parseInt`, `toString`, `Number`, and `String`.

### Options Compared

1. **toString**: 
   - **Benchmark Definition**: `var res = intA.toString()`
   - **Description**: The `toString` method is called on a number (`intA`), converting it directly to its string representation.
   - **Pros**: It is straightforward and effective for converting numbers to strings; it's a native method that is generally fast for this purpose.
   - **Cons**: It’s less flexible for parsing strings back to numbers.

2. **parseInt**:
   - **Benchmark Definition**: `var res = parseInt(strB);`
   - **Description**: The `parseInt` function reads a string and converts it to an integer. It considers the first part of the string until it hits a character that is not part of a number.
   - **Pros**: Good for converting strings to integers, especially when dealing with user input or parsing.
   - **Cons**: It can be sensitive to the format of the string and may lead to unexpected results if the string is not well-formed.

3. **Number**:
   - **Benchmark Definition**: `var res = Number(strB);`
   - **Description**: The `Number` function converts a string to a number (either integer or float).
   - **Pros**: More versatile than `parseInt` since it can handle floating-point numbers and will return `NaN` for invalid inputs. It adheres to the value of the string more faithfully.
   - **Cons**: May be slightly slower than `parseInt` in certain scenarios primarily focused on integers.

4. **String**:
   - **Benchmark Definition**: `var res = String(intA);`
   - **Description**: The `String` function is used to convert the given number or object into a string representation.
   - **Pros**: Easy to understand and adequate for most types to string conversion.
   - **Cons**: Generally, it adds a bit of overhead compared to the more direct `toString` method for number-to-string conversions.

### Benchmark Results

The benchmark results indicate the number of executions per second for each method when run in the same environment (Chrome version 135 on Windows). Here are the key takeaways from the performance:

- **parseInt**: 189,673,936 executions/second - Fastest method, indicative of its efficiency for converting strings to integers.
- **Number**: 174,174,064 executions/second - Slightly slower than `parseInt` but still performant, with more flexible parsing capabilities.
- **toString**: 99,424,824 executions/second - Slower than the previous two but still quite fast, suitable for straightforward conversions from number to string.
- **String**: 94,253,256 executions/second - The slowest in this benchmark context but still a valid and clear approach to convert data types.

### Considerations

- When choosing a method for your application, it's crucial to consider both the type of data you are converting and the context in which these methods are used. If you need to interpret user input (e.g., from a form), `parseInt` or `Number` would be more appropriate. If you are simply converting a number to a string for display purposes, then `toString` or `String` would be optimal.
- Performance can vary based on the JavaScript engine and the environment (browser vs. Node.js, for example), so it's a good practice to benchmark in the context in which your code will run.

### Alternatives

Apart from the approaches outlined above, other alternatives can include:

- **Template Literals / String Interpolation**: Using backticks, you can embed variables directly into strings, e.g., `` `${intA}` ``, which might offer clarity at a slight performance cost.
- **Concatenation**: Concatenating an empty string to a number, e.g., `intA + ""`, which also converts the number to a string but is not as explicit as the other methods.

Overall, developers should select methods based on the specific requirements of the task while considering readability, performance, and maintainability.

Related benchmarks:

parseInt vs toString (version: 1)

Comparing performance of: toString vs parseInt vs Number vs String

Created: 6 days ago by: Guest

Jump to the latest result

toString

parseInt

Number

String

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model gpt-4o-mini, generated 5 days ago):