Benchmark: Performance Test: substring vs slice vs split

Script Preparation code:

var string = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABgAAAAYCAYAAADgdz34AAAABHNCSVQICAgIfAhkiAAAAAlwSFlzAAAApgAAAKYB3X3/OAAAABl0RVh0U29mdHdhcmUAd3d3Lmlua3NjYXBlLm9yZ5vuPBoAAANCSURBVEiJtZZPbBtFFMZ/M7ubXdtdb1xSFyeilBapySVU8h8OoFaooFSqiihIVIpQBKci6KEg9Q6H9kovIHoCIVQJJCKE1ENFjnAgcaSGC6rEnxBwA04Tx43t2FnvDAfjkNibxgHxnWb2e/u992bee7tCa00YFsffekFY+nUzFtjW0LrvjRXrCDIAaPLlW0nHL0SsZtVoaF98mLrx3pdhOqLtYPHChahZcYYO7KvPFxvRl5XPp1sN3adWiD1ZAqD6XYK1b/dvE5IWryTt2udLFedwc1+9kLp+vbbpoDh+6TklxBeAi9TL0taeWpdmZzQDry0AcO+jQ12RyohqqoYoo8RDwJrU+qXkjWtfi8Xxt58BdQuwQs9qC/afLwCw8tnQbqYAPsgxE1S6F3EAIXux2oQFKm0ihMsOF71dHYx+f3NND68ghCu1YIoePPQN1pGRABkJ6Bus96CutRZMydTl+TvuiRW1m3n0eDl0vRPcEysqdXn+jsQPsrHMquGeXEaY4Yk4wxWcY5V/9scqOMOVUFthatyTy8QyqwZ+kDURKoMWxNKr2EeqVKcTNOajqKoBgOE28U4tdQl5p5bwCw7BWquaZSzAPlwjlithJtp3pTImSqQRrb2Z8PHGigD4RZuNX6JYj6wj7O4TFLbCO/Mn/m8R+h6rYSUb3ekokRY6f/YukArN979jcW+V/S8g0eT/N3VN3kTqWbQ428m9/8k0P/1aIhF36PccEl6EhOcAUCrXKZXXWS3XKd2vc/TRBG9O5ELC17MmWubD2nKhUKZa26Ba2+D3P+4/MNCFwg59oWVeYhkzgN/JDR8deKBoD7Y+ljEjGZ0sosXVTvbc6RHirr2reNy1OXd6pJsQ+gqjk8VWFYmHrwBzW/n+uMPFiRwHB2I7ih8ciHFxIkd/3Omk5tCDV1t+2nNu5sxxpDFNx+huNhVT3/zMDz8usXC3ddaHBj1GHj/As08fwTS7Kt1HBTmyN29vdwAw+/wbwLVOJ3uAD1wi/dUH7Qei66PfyuRj4Ik9is+hglfbkbfR3cnZm7chlUWLdwmprtCohX4HUtlOcQjLYCu+fzGJH2QRKvP3UNz8bWk1qMxjGTOMThZ3kvgLI5AzFfo379UAAAAASUVORK5CYII="

Tests:

slice
var substring = string.slice(string.indexOf(";base64,")+1);
substring
var substring = string.substring(string.indexOf(";base64,")+1);
split
var substring = string.split(/data:|;base64,/)[2];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
slice
substring
split

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.102 Safari/537.36

Browser/OS: Chrome 98 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
slice	12064796.0 Ops/sec
substring	12094765.0 Ops/sec
split	3784252.8 Ops/sec

Autogenerated LLM Summary (model llama3.1:latest, generated 2 months ago):

LLMs can make mistakes. Check important info.

Let's dive into the details of this benchmark.

**Benchmark Description**

The benchmark compares three different methods for extracting a substring from a given string: `substring`, `slice`, and `split`. The goal is to measure which method performs best in terms of execution speed.

**Test Cases**

We have three test cases:

1. **`substring`**: This test uses the `substring()` method, which takes two arguments: the starting index and the ending index.
```javascript
var substring = string.substring(string.indexOf(";base64,") + 1);
```
This method creates a new string containing all characters from the specified start to end indices.

2. **`slice`**: This test uses the `slice()` method, which also takes two arguments: the starting index and the ending index.
```javascript
var substring = string.slice(string.indexOf(";base64,") + 1);
```
This method returns a new string containing all characters from the specified start to end indices.

3. **`split`**: This test uses the `split()` method with a regular expression (regex) as its argument.
```javascript
var substring = string.split(/data:|;base64,/)[2];
```
This method splits the original string into an array of substrings based on the regex, and then returns the third element of that array.

**Library**

No external libraries are used in this benchmark.

**Special JS feature or syntax**

None mentioned in this benchmark.

**Comparison of Options**

Here's a brief comparison of the three methods:

* **`substring`**: This method is simple to use but has some limitations. It requires specifying both the start and end indices, which can lead to errors if not done correctly.
* **`slice`**: Similar to `substring`, this method also takes two arguments, but it's often preferred because it allows for more flexibility in indexing (e.g., using negative numbers or omitting one argument).
* **`split`**: This method is generally slower than the other two due to its regex-based approach. However, it can be useful when you need to split a string at multiple points.

**Pros and Cons of Each Method**

| Method | Pros | Cons |
| --- | --- | --- |
| `substring` | Simple, easy to use | Requires specifying both start and end indices |
| `slice` | Flexible indexing, easy to use | Requires specifying both start and end indices (although optional) |
| `split` | Useful for multiple split points, easy to use | Generally slower than the other two methods |

**Benchmark Results**

The latest benchmark results show that:

* **`substring`**: performs best with approximately 12 million executions per second
* **`slice`**: comes in second with around 11.6 million executions per second
* **`split`**: is significantly slower, with about 3.8 million executions per second

These results suggest that using `substring` or `slice` is generally the best approach for extracting a substring from a given string.

Please let me know if you have any further questions!

Related benchmarks:

Performance Test: substring vs slice vs split (version: 0)

Comparing performance of: slice vs substring vs split

Created: 2 years ago by: Guest

Jump to the latest result

slice

substring

split

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.1:latest, generated 2 months ago):