Since September 2023, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The size-adjust CSS descriptor for the @font-face at-rule defines a multiplier for glyph outlines and metrics associated with this font. This makes it easier to harmonize the designs of various fonts when rendered at the same font size.
The size-adjust descriptor behaves in a similar fashion to the font-size-adjust property. It calculates an adjustment per font by matching ex heights.
size-adjust: 90%;
<percentage>A <percentage> value with an initial value of 100%.
All metrics associated with this font are scaled by the given percentage. This includes glyph advances, baseline tables, and overrides provided by @font-face descriptors.
| Related at-rule | @font-face |
|---|---|
| Initial value | 100% |
| Percentages | as specified |
| Computed value | as specified |
size-adjust =
<percentage [0,∞]>
The size-adjust property can help when overriding the metrics of a fallback font to better match those of a primary web font.
@font-face {
font-family: web-font;
src: url("https://example.com/font.woff");
}
@font-face {
font-family: local-font;
src: local("Local Font");
size-adjust: 90%;
}
| Specification |
|---|
| CSS Fonts Module Level 5> # size-adjust-desc> |
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
size-adjust |
92 | 92 | 92 | 78 | 17 | 92 | 92 | No | 17 | 16.0 | 92 | 17 |
font-display descriptorfont-family descriptorfont-weight descriptorfont-style descriptorfont-stretch descriptorfont-feature-settingsfont-variation-settings descriptorsrc descriptorunicode-range descriptorfont-size-adjust property
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https://developer.mozilla.org/en-US/docs/Web/CSS/@font-face/size-adjust