Benchmark: Performance Test: substring vs substr vs slice with StartIndex

Script Preparation code:

var string = "I am the god of hellfire, and I bring you..."

Tests:

slice
var substring = string.slice(1);
substring
var substring = string.substring(1);
substr
var substring = string.substr(1);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
substring
substr

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.2 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
slice	15878320.0 Ops/sec
substring	16661222.0 Ops/sec
substr	12722896.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Measuring performance differences between various JavaScript methods is an essential task for any web developer or engineer. Let's break down the benchmark test case provided by MeasureThat.net.

**Benchmark Definition**

The main question being tested here is how to get a substring from a string in JavaScript. The three methods being compared are:

1. `slice()`: Returns a new string containing from the start index (0) up to but not including the end index.
2. `substring()`: Returns a new string containing from the start index (0) up to but not including the end index.
3. `substr()`: Returns a new string containing from the start index (0) up to and including the end index.

**Options Compared**

Each of these methods has its own strengths and weaknesses:

* **`slice()`**: Pros: concise, fast, and widely supported. Cons: can be less readable than other options. `slice()` is generally considered the most efficient way to get a substring in JavaScript.
* **`substring()`**: Pros: more readable than `slice()`, easy to understand for developers familiar with this method. Cons: slightly slower than `slice()`. This method was widely used before `slice()` became the standard, but its use has decreased over time.
* **`substr()`**: Pros: more concise and readable than `substring()`, can be faster in some cases. Cons: less consistent behavior across browsers and versions (e.g., some older browsers may use a different syntax). This method is generally considered less efficient than `slice()`.

**Library**

There is no explicit library being used in this benchmark test case. However, it's worth noting that if you're using a library like Lodash, which provides the `pick` function, it might be used to get a substring.

**Special JS feature or syntax**

This benchmark does not explicitly use any special JavaScript features or syntax. It simply tests three standard methods for getting a substring from a string.

**Other Considerations**

When choosing between these methods, consider the following factors:

* Performance: If speed is critical, `slice()` is likely your best choice.
* Readability: If code readability is important, `substring()` might be a better option.
* Consistency: If you need to support older browsers or versions that don't use `slice()`, `substr()` or `substring()` might be necessary.

**Alternatives**

If you're looking for alternative methods to get a substring in JavaScript, consider:

* Using regular expressions (e.g., `string.match(new RegExp('...'))`) with the `g` flag to extract substrings.
* Utilizing the `String.prototype.slice()` or `String.prototype.substr()` functions directly on string literals or template literals.

Keep in mind that these alternatives might have varying degrees of performance, readability, and browser support.

Related benchmarks:

Performance Test: substring vs substr vs slice with StartIndex (version: 0)

Comparing performance of: slice vs substring vs substr

Created: one year ago by: Guest

Jump to the latest result

slice

substring

substr

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):