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Table of Contents
Notes and FAQs
Practical application suggestions
Accessibility and compatibility
Home Web Front-end HTML Tutorial How to group options in a select element with ?

How to group options in a select element with ?

Jul 15, 2025 am 03:02 AM

In HTML forms, you can use the <optgroup> tag to group the drop-down options. 1. <optgroup> must include label attribute as group name; 2. Each group contains multiple <option>; 3. Nested <optgroup> is not allowed; 4. Group names are not optional; 5. The style is thick and indented by default but varies from browser to browser; 6. Suitable for scenarios such as region and product classification; 7. Good compatibility, supports mainstream browsers and facilitates accessibility; 8. If you need a highly customized appearance, it is recommended to use a third-party component library.

How to group options in a select element with <optgroup>?

In an HTML form, if you have a set of options (such as country, color, category, etc.) and want to display them by category, you can use the <optgroup></optgroup> tag. It makes the drop-down menu look clearer and more organized.

How to group options in a select element with <optgroup>? ?" />

Grouping options using <optgroup></optgroup>

<optgroup></optgroup> is a tag specifically used to group multiple <option></option> in <select></select> elements. Each <optgroup></optgroup> must contain a label attribute that defines the title of the group.

The basic structure is as follows:

How to group options in a select element with <optgroup>? ?" />
 <select>
  <optgroup label="Fruit">
    <option value="apple">Apple</option>
    <option value="banana">Banana</option>
  </optgroup>
  <optgroup label="vegetables">
    <option value="carrot">Carrot</option>
    <option value="broccoli">Broccoli</option>
  </optgroup>
</select>

In this way, the drop-down box rendered by the browser will be divided into two categories: "fruit" and "vegetable". Each category is the corresponding options.


Notes and FAQs

  • Cannot nest <optgroup> : HTML does not allow another <optgroup> to be placed in one <optgroup> .
  • Group name cannot be selected : When the user clicks the drop-down box, he can only select the specific <option> and cannot select the label of <optgroup> .
  • Style limits : By default, the text of <optgroup> is bolded and indented, but different browser styles may vary slightly. If you want to unify the appearance, you may need to replace the native select control with JavaScript.

Practical application suggestions

In development, <optgroup> is particularly suitable for use in the following scenarios:

How to group options in a select element with <optgroup>? ?" />
  • Regional selection (such as country/province)
  • Product categories (such as electronic products, clothing, food)
  • Color or size grouping

For example, suppose you are doing a product filtering function and want to classify colors by cold and warm colors:

 <select>
  <optgroup label="Cool Tone">
    <option value="blue">blue</option>
    <option value="green">Green</option>
  </optgroup>
  <optgroup label="warm tones">
    <option value="red">Red</option>
    <option value="orange">orange</option>
  </optgroup>
</select>

This makes it easier for users to find the color type they want.


Accessibility and compatibility

<optgroup></optgroup> is well supported in mainstream browsers, including Chrome, Firefox, Safari, and Edge. For screen readers, label are also read out, which helps improve accessibility.

But it should be noted:

  • Some mobile browsers have weak style control
  • If you need a highly customizable look, it is recommended to consider using a third-party component library (such as React Select)

Basically that's it. While simple, it is very practical when organizing a large number of options.

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