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system-ui value for font-family

The font-family-system-ui property sets a default value of the font family. It may be used to supply a user interface font as fallback when none is specified, such as in cases of font formatting that blocks or otherwise fails to parse correctly.

Last updated on : 2025-11-11

Browser Versions

Edge

Firefox

Chrome

Safari

Opera

5.5 - 11

12 - 18

79 - 142

2 - 42

43 - 91

92 - 147

4 - 52

53 - 55

56 - 145

3.2 - 8

9.1 - 10.1

11 - 26.2

9.5 - 42

43 - 122

Fully Supported

Partially

No Support

Formal Definition

Inherited

yes

Applies to

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

Initial value

depends on user agent

Animation type

discrete

Computed value

as specified

Specifications

CSS Fonts Module Level 4 # generic-font-families CSS Fonts Module Level 4 # font-family-prop

Syntax

/* A font family name and a generic family name */
 font-family: "Gill Sans Extrabold", sans-serif;
 font-family: "Goudy Bookletter 1911", sans-serif;
 /* A generic family name only */
 font-family: serif;
 font-family: sans-serif;
 font-family: monospace;
 font-family: cursive;
 font-family: fantasy;
 font-family: system-ui;
 font-family: ui-serif;
 font-family: ui-sans-serif;
 font-family: ui-monospace;
 font-family: ui-rounded;
 font-family: emoji;
 font-family: math;
 font-family: fangsong;
 /* Global values */
 font-family: inherit;
 font-family: initial;
 font-family: revert;
 font-family: unset;

Browser Compatibility

system-ui value for font-family on IE is not supported on any IE versions.

system-ui value for font-family on Edge is fully supported on 79-142, and not supported on 12-18 Edge versions.

system-ui value for font-family on Firefox is fully supported on 92-147, partially supported on 43-91, and not supported on 2-42 Firefox versions.

system-ui value for font-family on Chrome is fully supported on 56-145, partially supported on 53-55, and not supported on 4-52 Chrome versions.

system-ui value for font-family on Safari is fully supported on 11-26.2, partially supported on 9.1-10.1, and not supported on 3.2-8 Safari versions.

system-ui value for font-family on Opera is fully supported on 43-122, and not supported on 9.5-42 Opera versions.

system-ui value for font-family on Safari on iOS is fully supported on 11-26.1, partially supported on 9.3-10.3, and not supported on 3.2-8 Safari on iOS versions.

system-ui value for font-family on Android Browser is fully supported on 97-142, and not supported on 2.3-4 Android Browser versions.

system-ui value for font-family on Opera Mobile is fully supported on 64-80, and not supported on 10-12 Opera Mobile versions.

system-ui value for font-family on Chrome for Android is fully supported on all Chrome for Android versions.

system-ui value for font-family on Firefox for Android is fully supported on all Firefox for Android versions.

system-ui value for font-family on Samsung Internet is fully supported on 6.2-29, and not supported on 4-5 Samsung Internet versions.

Browser Support for system-ui value for font-family

system-ui value for font-family on Chrome

system-ui value for font-family on Safari

system-ui value for font-family on Firefox

system-ui value for font-family on Internet Explorer

system-ui value for font-family on Opera

system-ui value for font-family on Edge

References

Data sourced from

High

Overall Browser Compatibility Score

Note:system-ui value for font-family shows a browser compatibility score of 92. 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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