Benchmark: jQuery vs getElementById vs querySelector

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 = $("#testElement")[0];
getElementById
var el = document.getElementById('testElement');
querySelector
var el = document.querySelector("#testElement");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
jQuery
getElementById
querySelector

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**Benchmark Overview**

The provided benchmark compares the speed of getting an element by its ID using three approaches: jQuery, `document.getElementById()`, and `document.querySelector()`.

**Library and Purpose**

* jQuery is a popular JavaScript library that provides an easy-to-use API for DOM manipulation. In this benchmark, it's used to select elements based on their ID.
* The `document.getElementById()` method is a native JavaScript function that retrieves an element by its ID.
* The `document.querySelector()` method is also a native JavaScript function that retrieves an element based on a CSS selector.

**Options Compared**

The three options are compared in terms of their execution speed. Each test case measures how many times the code within the benchmark definition is executed per second (ExecutionsPerSecond).

**Pros and Cons of Different Approaches**

* **jQuery**: Pros:
	+ Easy to use, especially for developers familiar with jQuery.
	+ Can be faster than native methods due to its optimized implementation.
Cons:
	+ Adds an extra library dependency, which can increase the benchmark's overhead.
	+ May not perform as well on older browsers that don't support jQuery.
* **`document.getElementById()`**: Pros:
	+ Fast and lightweight, making it suitable for small scripts.
	+ Native JavaScript function, so no additional dependencies are required.
Cons:
	+ Requires more DOM traversal, which can be slower than direct ID-based selection.
	+ May not work as expected if the element is hidden or has a dynamic ID.
* **`document.querySelector()`**: Pros:
	+ Similar to `getElementById()`, but offers more flexibility with CSS selectors.
	+ Can be faster than `getElementById()` for elements that have multiple IDs.
Cons:
	+ May be slower than `getElementById()` due to the overhead of parsing CSS selectors.
	+ Less intuitive than `getElementById()` or jQuery.

**Other Considerations**

* **Browser support**: The benchmark results are specific to Chrome 129 on a Windows Desktop. Different browsers may behave differently, especially when it comes to caching and optimization.
* **HTML structure**: The provided HTML structure is simple and optimized for the test cases. In real-world scenarios, the DOM tree can be much more complex, affecting the performance of these methods.

**Alternatives**

Other alternatives for selecting elements by ID include:

* `document.querySelector('#testElement')`: This method uses a single # character instead of the dot notation.
* `element.ownerDocument.getElementById('testElement')`: This method retrieves an element from its parent document if it's not the same as the current window's document.

Keep in mind that while these alternatives exist, they might not offer significant performance differences compared to the native methods used in the benchmark.

Latest run results:

Run details: (Test run date: 17 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0

Browser/OS: Firefox 115 on Linux

View result in a separate tab

Test name	Executions per second
jQuery	6857227.0 Ops/sec
getElementById	10846287.0 Ops/sec
querySelector	4307912.0 Ops/sec

Related benchmarks:

jQuery vs getElementById vs querySelector (version: 1)

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

Comparing performance of: jQuery vs getElementById vs querySelector

Created: 4 years ago by: Registered User

Jump to the latest result

jQuery

getElementById

querySelector

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):