Benchmark: slice vs substr vs substring

Script Preparation code:

var example = 'hello world !'

Tests:

slice
var result = example.slice(0, 6)
substr
var result = example.substr(0, 6)
substring
var result = example.substring(0, 6)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
substr
substring

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/136.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 136 on Android

View result in a separate tab

Test name	Executions per second
slice	94592480.0 Ops/sec
substr	110375856.0 Ops/sec
substring	108259528.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided benchmark compares the performance of three string slicing methods in JavaScript: `slice`, `substr`, and `substring`. The test is designed to measure the execution time of each method when only a start index is specified.

**Methods Compared**

1. **`slice()`**: This method returns a new string containing all characters from the original string, starting at the specified index.
2. **`substr()`**: This method also returns a new string containing all characters from the original string, starting at the specified index. However, unlike `slice()`, `substr()` does not allow specifying an end index. The end index is assumed to be the length of the string if no second argument is provided.
3. **`substring()`**: This method returns a new string containing all characters from the original string, starting at the specified start index and ending at the specified end index.

**Pros and Cons of Each Approach**

1. **`slice()`**:
	* Pros: Fastest execution time among the three methods due to its direct access to the string's internal buffer.
	* Cons: May not be compatible with all browsers or environments, as it relies on the underlying string implementation.
2. **`substr()`**:
	* Pros: Simple and widely supported across browsers and environments.
	* Cons: Slower execution time compared to `slice()`, especially for large strings.
3. **`substring()`**:
	* Pros: More intuitive and flexible than `substr()`, allowing the specification of both start and end indices.
	* Cons: May be slower than `slice()` due to its additional overhead.

**Library Usage**

None of the methods use a library or any external dependencies in this benchmark. The test focuses solely on the native JavaScript string slicing methods.

**Special JS Features or Syntax**

No special JavaScript features or syntax are used in this benchmark.

**Alternative Approaches**

In addition to the three standard string slicing methods, other approaches could be considered:

1. **Using a library**: A dedicated string manipulation library like jQuery or Lodash could provide optimized and feature-rich string slicing functionality.
2. **Using regular expressions**: Regular expressions can be used to extract substrings from strings, but this approach may be slower than the standard string slicing methods.
3. **Using a buffer-based implementation**: For large strings, using a buffer-based implementation might offer better performance compared to the standard string slicing methods.

In conclusion, the benchmark provides a clear comparison of the performance of three native JavaScript string slicing methods: `slice()`, `substr()`, and `substring()`. While each method has its pros and cons, `slice()` is generally considered the fastest approach due to its direct access to the underlying string's internal buffer.

Related benchmarks:

slice vs substr vs substring (version: 0)

Compares slice, substr and substring to each other when there is only a start index

Comparing performance of: slice vs substr vs substring

Created: 7 years ago by: Guest

Jump to the latest result

slice

substr

substring

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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