| Value | Meaning |
| negative | element will be focusable, but it should not be reachable via sequential keyboard navigation |
| 0 | element will be focusable and reachable through keyboard sequential navigation, but it’s relative order is defined by the platform convention |
| positive | element must be focusable and accessible via sequential keyboard navigation; it’s relative order will be defined by the attribute value: the sequential follow the increasing number of the tabindex |
Add an element to the tabbing order
<div tabindex="0">Some button</div>
Note: Try to use a native HTML button or an a tag where appropriate.
Remove an element from the tabbing order
<button tabindex="-1">This button will not be reachable by tab</button>
The element will be removed from the tabbing order but will still be focusable.
Define a custom tabbing order (not recommended)
<div tabindex="2">Second</div> <div tabindex="1">First</div>
Positive values will insert the element at the tabbing order position of its respective value. Elements without
preference (i.e. tabindex=”0″ or native elements such as button and a) will be appended after those with
preference.
Positive values are not recommended as they disrupt the expected behavior of tabbing and might confuse people
who rely on screenreaders. Try to create a natural order by rearranging your DOM structure.