Benchmark: getElementById vs querySelector custom

HTML Preparation code:

<div class="cell">
            
<div class="grid-x grid-padding-x">
  <div id="size-configuration-table" class="cell small-24 large-6">
    <table class="vertical-table">
      <thead>
        <tr>
          <th class="table-title h6" colspan="2">
            Size Configuration
          </th>
        </tr>
      </thead>
      <tbody>
        <tr>
          <th> Id </th>
          <td> 98 </td>
        </tr>

        <tr>
          <th> Categories </th>
          <td>
            <ul class="no-bullet">
                  <li>
                    <a href="/earth/categories/530">Ανδρικά Παντελόνια</a>
                  </li>
            </ul>
          </td>
        </tr>

        <tr>
          <th> Manufacturers </th>
          <td>
            <ul class="no-bullet">
                <li>
                  <a href="/earth/manufacturers/1282">Lacoste</a>
                </li>
            </ul>
          </td>
        </tr>

        <tr>
          <th> Gender </th>
          <td>
            <ul class="no-bullet">
                <li>
                  Men
                </li>
            </ul>
          </td>
        </tr>

        <tr>
          <th> Numeric system </th>
          <td> Manufacturer </td>
        </tr>

        <tr>
          <th> Target system </th>
          <td> International (S,M,L) </td>
        </tr>

        <tr>
          <th> Status </th>
          <td>
            <span class="label warning">
              Draft
            </span>
          </td>
        </tr>
      </tbody>
    </table>
  </div>

  <div id="size-chart" class="cell small-24 large-18">
    <table class="vertical-table">
      <thead>
        <tr>
          <th class="table-title h6" colspan="14">
            Size Chart
          </th>
        </tr>
        <tr>
          <th id="lala" class="text-center system">
            System
          </th>
          <th colspan="13" class="text-center sizes">
            Sizes
          </th>
        </tr>
      </thead>
      <tbody>
            <tr>
              <td>
                <b> IS </b>
              </td>
                <td> XS </td>
                <td> S </td>
                <td> S </td>
                <td> S </td>
                <td> M </td>
                <td> M </td>
                <td> L </td>
                <td> L </td>
                <td> XL </td>
                <td> XL </td>
                <td> XXL </td>
                <td> XXL </td>
                <td> XXXL </td>
            </tr>
            <tr>
              <td>
                <b> MNF </b>
              </td>
                <td> 34 </td>
                <td> 36 </td>
                <td> 36 </td>
                <td> 38 </td>
                <td> 40 </td>
                <td> 42 </td>
                <td> 44 </td>
                <td> 46 </td>
                <td> 48 </td>
                <td> 50 </td>
                <td> 52 </td>
                <td> 54 </td>
                <td> 56 </td>
            </tr>
            <tr>
              <td>
                <b> WL </b>
              </td>
                <td> 28 </td>
                <td> 28 </td>
                <td> 29 </td>
                <td> 30 </td>
                <td> 32 </td>
                <td> 33 </td>
                <td> 34 </td>
                <td> 36 </td>
                <td> 38 </td>
                <td> 40 </td>
                <td> 42 </td>
                <td> 44 </td>
                <td> 46 </td>
            </tr>
      </tbody>
    </table>
  </div>
</div>

          </div>

Script Preparation code:

var parentElement = document.getElementById('size-chart');

Tests:

getelementById
document.getElementById('lala')
querySelector
parentElement.querySelector('#lala');

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getelementById
querySelector

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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 difference between `getElementById` and `querySelector` methods in JavaScript, specifically when used to select an element by its id.

**Test Cases**

There are two test cases:

1. **getelementById**: This test case uses the `document.getElementById('lala')` method to retrieve an element from the DOM.
2. **querySelector**: This test case uses the `parentElement.querySelector('#lala')` method to retrieve an element from the DOM, where `parentElement` is a previously retrieved element.

**Options Compared**

The benchmark compares two options:

1. **getElementById**: A traditional method for retrieving an element by its id.
2. **querySelector**: A more modern method for retrieving elements by their selectors, which can also be used to retrieve elements by their ids.

**Pros and Cons of Each Approach**

* **getElementById**:
	+ Pros: Simple and widely supported, no additional library or configuration required.
	+ Cons: Can be slower than `querySelector` due to the need to search the entire DOM tree.
* **querySelector**:
	+ Pros: More powerful and flexible, can also be used for other types of selections (e.g., classes, attributes).
	+ Cons: Requires a previously retrieved element (`parentElement`) or a more complex CSS selector.

**Library Used**

The `querySelector` method uses the W3C Selectors API, which is a standardized way of selecting elements in HTML and XML documents. The `querySelector` method is part of the DOM4 specification.

**Benchmark Results**

The latest benchmark results show that:

* **querySelector** outperforms **getElementById** by approximately 10% in terms of executions per second.
* The performance difference between the two methods is relatively small, suggesting that both methods are efficient and well-optimized.

Overall, this benchmark highlights the trade-offs between traditional `getElementById` and more modern `querySelector` methods for retrieving elements from the DOM. While `querySelector` offers greater flexibility and power, it also requires a previously retrieved element or a more complex CSS selector, which can add complexity to the code.

Related benchmarks:

getElementById vs querySelector custom (version: 0)

Comparing performance of: getelementById vs querySelector

Created: 6 years ago by: Guest

Jump to the latest result

getelementById

querySelector

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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