Benchmark: getElementById vs querySelector vs getElementsByName

HTML Preparation code:

<div id="testElement" name="testElem"></div>

Tests:

getElementById
var el = document.getElementById('testElement'); var className = el.className;
querySelector
var el = document.querySelector('#testElement'); var className = el.className;
getElementsByName
var el = document.getElementsByName('testElem'); var className = el.className;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getElementById
querySelector
getElementsByName

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/605.1.15 (KHTML, like Gecko) Version/17.3 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
getElementById	5868315.5 Ops/sec
querySelector	3360567.8 Ops/sec
getElementsByName	5939290.5 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 measures the performance of three JavaScript methods to access an HTML element: `document.getElementById()`, `document.querySelector()`, and `document.getElementsByName()`.

**Method Comparison**

1. **`document.getElementById()`**: This method returns the first element with the specified ID in the document. If no element is found, it returns `null`.
	* Pros:
		+ Fastest among the three methods.
		+ Simple to use.
	* Cons:
		+ May return `null` if no element is found.
2. **`document.querySelector()`**: This method returns the first element that matches the specified CSS selector in the document.
	* Pros:
		+ More flexible than `getElementById()`, as it allows for more complex selectors.
	* Cons:
		+ Generally slower than `getElementById()`.
3. **`document.getElementsByName()`**: This method returns a NodeList containing all elements with the specified name attribute value in the document.
	* Pros:
		+ May be faster than `querySelector()` if the element is found in the first iteration of the DOM traversal.
	* Cons:
		+ Less flexible than `querySelector()`, as it only searches for elements by name, not CSS selectors.

**Library and Special JS Features**

None of the benchmark cases use a specific JavaScript library. However, they do demonstrate basic HTML and CSS concepts.

No special JavaScript features or syntax are used in these test cases.

**Other Alternatives**

If you need to access an HTML element, consider the following alternatives:

* `document.querySelector()` with a more complex CSS selector.
* A library like jQuery, which provides its own set of methods for accessing elements (e.g., `$()`, `.class()`).
* A framework like React or Angular, which provide their own sets of methods and tools for working with HTML elements.

In general, the choice of method depends on the specific requirements of your application. If you need to access an element by its ID, `document.getElementById()` is usually a good choice. For more complex scenarios, `querySelector()` may be a better option.

Related benchmarks:

getElementById vs querySelector vs getElementsByName (version: 0)

Comparing performance of: getElementById vs querySelector vs getElementsByName

Created: 2 years ago by: Guest

Jump to the latest result

getElementById

querySelector

getElementsByName

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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