Benchmark: getElementById vs id

HTML Preparation code:

<div id="test"></div>

Tests:

id
let myvar = test;
getElementById
let myvar = document.getElementById("test");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
id
getElementById

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:136.0) Gecko/20100101 Firefox/136.0

Browser/OS: Firefox 136 on Mac OS X 10.15

View result in a separate tab

Test name	Executions per second
id	893865.6 Ops/sec
getElementById	3666313.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its test cases to understand what is being tested.

**Benchmark Definition**

The benchmark measures the performance of two ways to access an HTML element by its ID: using the `id` property directly and using the `document.getElementById()` method.

The benchmark definition JSON provides a reference for the test cases, but it's not actually used in the execution. Instead, the test cases are defined in the "Benchmark Definition" section, which contains two individual test cases:

1. **id**: This test case creates a variable `myvar` using the `id` property directly on the HTML element (`<div id="test"></div>`).
2. **getElementById**: This test case creates a variable `myvar` using the `document.getElementById()` method to access the same HTML element.

**Options Compared**

The two options being compared are:

1. Directly accessing an element by its ID using the `id` property (`let myvar = test;`)
2. Using the `document.getElementById()` method to access an element by its ID (`let myvar = document.getElementById("test");`)

**Pros and Cons**

- **Direct Access**: This approach is often faster because it avoids the overhead of a function call and can be optimized by the JavaScript engine.
- **`document.getElementById()` Method**: This approach provides a more explicit way to access elements, which can be beneficial for maintainability and readability. However, it may incur a slight performance penalty due to the function call.

**Other Considerations**

* The benchmark measures the execution time of both approaches on different browsers and devices.
* The test cases use a simple HTML element with an ID, making it easy to compare the performance of both methods.

**Library and Purpose**

There is no explicit library mentioned in the benchmark definition. However, `document` is a part of the DOM (Document Object Model), which provides an API for interacting with web pages. The `getElementById()` method is a part of this API, allowing developers to access elements by their ID.

**Special JS Feature or Syntax**

There are no special JavaScript features or syntax mentioned in the benchmark definition.

**Alternatives**

Some alternative ways to access an element by its ID include:

* Using the `querySelector()` or `querySelectorAll()` methods, which can be more flexible and powerful but may also incur a performance penalty.
* Using a library like jQuery, which provides a simple way to access elements using their IDs. However, this approach may introduce additional overhead due to the library's functionality.

In conclusion, the benchmark measures the performance of two common approaches to accessing an HTML element by its ID: direct access using the `id` property and the `document.getElementById()` method. The results provide insights into which approach is faster on different browsers and devices.

Related benchmarks:

getElementById vs id (version: 0)

Comparing performance of: id vs getElementById

Created: 2 years ago by: Guest

Jump to the latest result

id

getElementById

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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