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The tabindex attribute is used to control the focusability and Tab navigation order of web page elements. Correct use can improve accessibility; 1. tabindex="0" enables elements to enter the natural Tab stream in document order, which is suitable for custom interactive controls; 2. tabindex="-1" allows programming focus through JavaScript but does not participate in Tab order, and is often used in modal boxes or dynamic focus; 3. Avoid using positive values greater than 0, because it will disrupt the natural navigation order and damage the accessibility experience; priority should be followed by document structure, and coordinated with ARIA role and keyboard event processing to ensure accessibility best practices.
The tabindex
attribute in HTML5 controls the focusability and tab order of elements on a web page when users navigate using the Tab key (typically for keyboard accessibility). It helps make web content more accessible by allowing developers to define which elements can receive focus and in what sequence.

Here's how it works:
1. Managing Focus Order
By default, only interactive elements like links ( <a href></a>
), buttons, and form controls can receive keyboard focus and are navigable in the order they appear in the HTML. The tabindex
attribute lets you change this behavior for any element.

2. Three Types of tabindex Values
-
tabindex="0"
Makes the element focused and places it in the natural tab order (based on document source order).
Example:<div tabindex="0">This can now be focused with Tab</div>
Useful for making custom widgets (like a
<div>
used as a button) keyboard accessible. tabindex="-1"
Makes the element programmatically focused but removes it from the tab sequence . You can focus it via JavaScript (eg,element.focus()
), but users can't reach it by tabbing.
Commonly used for modal dialogs, headings, or elements that should be focused under certain conditions.tabindex="positive number"
(eg,1
,2
, etc.)
Elements with a positivetabindex
are focused in ascending order before anytabindex="0"
elements.
?? Avoid using positive values (especially above 0) — they disrupt natural document flow and hurt accessibility.Example (not recommended):
<button tabindex="1">Tab first</button> <button tabindex="2">Then this</button>
This can confuse screen reader users and should be avoided unless absolutely necessary.
3. Accessibility Best Practices
- Use
tabindex="0"
to include non-interactive elements in keyboard navigation when semantically appropriate (eg, custom controls). - Use
tabindex="-1"
to prepare elements for programmatic focus (like focusing a modal when opened). - Avoid
tabindex > 0
— it creates unpredictable navigation and is considered a bad practice. - Always ensure elements with
tabindex="0"
or-1
have appropriate ARIA roles and keyboard event handling if they act like interactive controls.
Summary
The tabindex
attribute is a powerful tool for enhancing keyboard navigation and accessibility when used correctly. Stick to 0
and -1
, follow the natural document order, and avoid disrupting the user's expected tab flow.
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