font-size-adjust

Baseline 2024

Newly available

Since ⁨July 2024⁩, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The font-size-adjust attribute allows authors to specify an aspect value for an element that will preserve the x-height of the first choice font in a substitute font.

Note: As a presentation attribute, font-size-adjust also has a CSS property counterpart: font-size-adjust. When both are specified, the CSS property takes priority.

You can use this attribute with the following SVG elements:

Usage notes

Default value	`none`
Value	`none` \| `<number>`
Animatable	Yes

none

Choose the size of the font based only on the font-size property.

<number>

Choose the size of the font so that its lowercase letters (as determined by the x-height of the font) are the specified number times the font-size.

The number specified should generally be the aspect ratio (ratio of x-height to font size) of the first choice font-family. This means that the first-choice font, when available, will appear the same size in browsers, whether or not they support font-size-adjust.

0 yields text of zero height (hidden text).