Benchmark: jQuery vs querySelector for classes

HTML Preparation code:

<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.1.0.min.js"></script>
<div id="testElement" class="test class list classes"></div>

Tests:

jQuery
var el = $(".classes")[0];
querySelector
var el = document.querySelector(".classes");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
jQuery
querySelector

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36

Browser/OS: Chrome 125 on Windows

View result in a separate tab

Test name	Executions per second
jQuery	1189575.1 Ops/sec
querySelector	4369048.0 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 explain the benchmark and its results.

**Benchmark Description**

The benchmark is designed to compare the speed of two approaches for selecting an element by its class in JavaScript:

1. **jQuery**: The jQuery library provides a convenient way to select elements using CSS selectors, including classes.
2. **Vanilla JS with getElementById and querySelector**: This approach uses the `getElementById` method (which doesn't work here since there's no id) and then queries the resulting element using the `querySelector` function.

**Options Compared**

The benchmark compares two options:

1. **jQuery**: Uses the jQuery library to select elements by class.
2. **Vanilla JS with getElementById and querySelector**: Uses the native JavaScript functions `getElementById` (not used here) and `querySelector`.

**Pros and Cons of Each Approach**

* **jQuery**:
	+ Pros:
		- Easy to use and convenient for common use cases.
		- Reduces boilerplate code.
	+ Cons:
		- Adds an extra dependency (the jQuery library).
		- May have performance overhead due to the abstraction layer.
* **Vanilla JS with getElementById and querySelector**:
	+ Pros:
		- No additional dependencies beyond native JavaScript functions.
		- Can be optimized for performance.
	+ Cons:
		- Requires manual CSS selector parsing and execution, which can add complexity.
		- May require more boilerplate code.

**Library: jQuery**

jQuery is a popular JavaScript library that simplifies DOM manipulation and event handling. In this benchmark, it's used to select elements by class using the `$(selector)` syntax. The library provides an abstraction layer over the native browser functionality, making it easier to work with elements.

**Special JS Feature or Syntax**

This benchmark doesn't use any special JavaScript features or syntax beyond CSS selectors and native functions like `querySelector`. However, some versions of JavaScript (like ECMAScript 2015+) might offer newer APIs for selecting elements by class, such as `classList` on DOM elements.

**Other Alternatives**

If you need to select elements by class in a JavaScript context without using jQuery or vanilla JS with `querySelector`, consider the following alternatives:

1. **Sizzle**: A CSS selector engine that's similar to jQuery's selector parsing algorithm.
2. **Query.js**: Another lightweight CSS selector library for JavaScript.
3. **DOM Traversals**: You can also use native DOM traversal methods, such as `NodeList.prototype.item` or `Array.prototype.forEach`, to iterate over elements and find matches.

Keep in mind that each of these alternatives has its own trade-offs and performance characteristics, so choose the one that best fits your needs.

Related benchmarks:

jQuery vs querySelector for classes (version: 0)

Comparing speed of getting element by id with jQuery vs Vanilla JS with getElementById and querySelector

Comparing performance of: jQuery vs querySelector

Created: one year ago by: Guest

Jump to the latest result

jQuery

querySelector

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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