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CSS font-size-adjust

The font-size-adjust property is used to adjust the size of fallback fonts so that uppercase and lowercase letters have approximately the same height. This makes converting between uppercase and lowercase easier.

Last updated on : 2025-03-16

Browser Versions

Edge

Firefox

Chrome

Safari

Opera

5.5 - 11

12 - 126

127 - 133

2 - 2

3.6 - 138

4 - 128

129 - 136

3.2 - 16

16.5 - 18.4

9.5 - 112

113 - 114

Fully Supported

Partially

No Support

Formal Definition

Inherited

yes

Applies to

all elements. It also applies to ::first-letter and ::first-line.

Initial value

none

Animation type

a number

Computed value

as specified

Specifications

CSS Fonts Module Level 5 # font-size-adjust-prop

Browser Compatibility

CSS font-size-adjust on IE is not supported on any IE versions.

CSS font-size-adjust on Edge is fully supported on 127-133, and not supported on 12-126 Edge versions.

CSS font-size-adjust on Firefox is fully supported on 3.6-138, and not supported on 2-2 Firefox versions.

CSS font-size-adjust on Chrome is fully supported on 129-136, and not supported on 4-128 Chrome versions.

CSS font-size-adjust on Safari is fully supported on 16.5-18.4, and not supported on 3.2-16 Safari versions.

CSS font-size-adjust on Opera is fully supported on 113-114, and not supported on 9.5-112 Opera versions.

CSS font-size-adjust on Safari on iOS is fully supported on 16.4-18.4, partially supported on 16.6-16.6, and not supported on 3.2-16.3 Safari on iOS versions.

CSS font-size-adjust on Android Browser is fully supported on 127-133, and not supported on 2.3-126 Android Browser versions.

CSS font-size-adjust on Opera Mobile is not supported on any Opera Mobile versions.

CSS font-size-adjust on Chrome for Android is fully supported on 127-133, and not supported on 97-126 Chrome for Android versions.

CSS font-size-adjust on Firefox for Android is fully supported on 104-135, and not supported on 95-101 Firefox for Android versions.

CSS font-size-adjust on Samsung Internet is not supported on any Samsung Internet versions.

Browser Support for CSS font-size-adjust

CSS font-size-adjust on Chrome

CSS font-size-adjust on Safari

CSS font-size-adjust on Firefox

CSS font-size-adjust on Internet Explorer

CSS font-size-adjust on Opera

CSS font-size-adjust on Edge

References

Data sourced from

Low

Overall Browser Compatibility Score

Note:CSS font-size-adjust shows a browser compatibility score of 48. This is a collective score out of 100 to represent browser support of a web technology. The higher this score is, the greater is the browser compatibility. The browser compatibility score is not a 100% reflection for every browser and the web technology support. However, it does give you an estimate on how much you should rely on a particular web technology in terms of browser compatibility.

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