Benchmark: DataAttribute vs Class Selector vs ID Selector vs Custom Attributes

HTML Preparation code:

<div class="hello" id="hello" data-hello uid="hello">Hello</div>

Tests:

data attribute
document.querySelector('[data-hello]');
class
document.querySelector('.hello');
id
document.querySelector('#hello');
uid
document.querySelector('[uid="hello"]');

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Firefox 5 runs

4.1M/s

class

4.1M/s

data attribute

3.6M/s

uid

3.5M/s

Fastest: id (1.2x faster)

View exact numbers

✓ id: 4,076,352 ops/sec
• class: 4,057,625 ops/sec
• data attribute: 3,628,566 ops/sec
• uid: 3,453,610 ops/sec

Results show median performance across all community submissions. Run this benchmark yourself to verify on your device.

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
data attribute
class
id
uid

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:146.0) Gecko/20100101 Firefox/146.0

Browser/OS: Firefox 146 on Windows

View result in a separate tab

4.7M/s

data attribute

4.6M/s

class

4.6M/s

uid

4.3M/s

View exact numbers

Test name	Executions per second
✓ id	4,707,752 Ops/sec
data attribute	4,646,132 Ops/sec
class	4,645,091 Ops/sec
uid	4,329,929 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks on MeasureThat.net.

The provided JSON represents a benchmark test case that compares the performance of four different approaches to select an HTML element:

1. **Data Attribute**: Using the `[data-hello]` attribute to select the element.
2. **Class Selector**: Using the `.hello` class selector to select the element.
3. **ID Selector**: Using the `#hello` ID selector to select the element.
4. **Custom Attributes**: Using a custom attribute called `uid` with the value "hello" to select the element.

**What are the options being compared?**

The test cases compare the performance of each approach in selecting the same HTML element. The benchmark measures the time it takes for each browser (in this case, Chrome 108) to execute each query on a desktop device running Mac OS X 10.15.7.

**Pros and Cons of each approach:**

1. **Data Attribute**: This approach is useful when you need to select an element based on a data attribute that is unique or relevant to the content of the element.
	* Pros: Flexible, doesn't require a predefined class or ID, can be used with dynamic content.
	* Cons: May not work if the attribute is not present or set correctly, can be slower than other approaches for performance-critical code.
2. **Class Selector**: This approach uses a CSS class to select an element. It's often faster and more efficient than data attributes because it's less computationally expensive.
	* Pros: Fast, reliable, and widely supported. Suitable for most use cases.
	* Cons: Requires a predefined class name, which may not be flexible or adaptable to dynamic content.
3. **ID Selector**: This approach uses an HTML ID to select an element. It's often faster than class selectors because it's more specific and direct.
	* Pros: Fast, reliable, and widely supported. Suitable for most use cases.
	* Cons: Requires a unique and predefined ID, which may not be flexible or adaptable to dynamic content.
4. **Custom Attributes**: This approach uses a custom attribute (in this case, `uid`) to select an element. It's similar to data attributes but is often used in more complex or proprietary systems.
	* Pros: Flexible, can be used with dynamic content. Suitable for specific use cases where other approaches don't work.
	* Cons: May not work if the attribute is not present or set correctly, can be slower than other approaches.

**Library and Purpose (if applicable)**

None of the provided benchmark test cases appear to rely on external libraries. However, MeasureThat.net provides a list of JavaScript libraries that you can use in your benchmarks for testing performance.

**Special JS feature or syntax**

There are no special JavaScript features or syntax mentioned in the provided information. The benchmark uses standard HTML and CSS selectors.

**Alternatives**

If you're interested in exploring alternative approaches to element selection, consider the following:

* Using `querySelectorAll()` instead of individual selector methods (e.g., `querySelector()`, `querySelectorAll()`).
* Using template literals or string interpolation to generate more dynamic selectors.
* Leveraging modern JavaScript features like `IntersectionObserver` or `requestAnimationFrame()` for performance-critical code.

Keep in mind that the specific approach you choose will depend on your project's requirements, performance constraints, and personal preferences. MeasureThat.net provides a valuable resource for benchmarking and comparing different approaches to element selection in JavaScript.

DataAttribute vs Class Selector vs ID Selector vs Custom Attributes (version: 0)

Comparing performance of: `data attribute vs class vs id vs uid`

Created: 3 years ago by: Guest

Go to the latest result

data attribute

class

id

uid

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Firefox 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

DataAttribute vs Class Selector vs ID Selector vs Custom Attributes (version: 0)

Comparing performance of: data attribute vs class vs id vs uid

Created: 3 years ago by: Guest

Go to the latest result

data attribute

class

id

uid

Historical Performance Data aggregated from 5 community runs

Desktop Results:

Firefox 5 runs

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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

Related benchmarks

Comparing performance of: `data attribute vs class vs id vs uid`