coderef

font-weightBaseline · Widely available

The font-weight CSS property controls the thickness of a font. It is set explicitly with the keyword bold or a number, or relative to the inherited thickness with the keywords bolder or lighter.

Supported in all major browsers for at least 30 months — safe to use without fallbacks. Baseline since Jul 29, 2015. Widely available since Jan 29, 2018.

How to use ↓Compare browsers

Browser support

DesktopChrome
1–1Not supported
2+Supportedsince May 21, 2009
Current: 155
Edge
12+Supportedsince Jul 29, 2015
Current: 154
Firefox
1+Supportedsince Nov 9, 2004
Current: 157
Safari
1+Supportedsince Jun 23, 2003
Current: 27
MobileChrome Android
18+Supportedsince Jun 27, 2012
Current: 155
Firefox Android
4+Supportedsince Mar 29, 2011
Current: 157
Safari iOS
1+Supportedsince Jun 29, 2007
Current: 27

How to use

This feature is Baseline widely available — use it freely, no fallback needed.

Example

Full syntax and examples are on MDN: font-weight.

Feature detection

CSS · check before using
@supports (font-weight: initial) {
  /* styles that rely on font-weight */
}

/* or in JavaScript */
if (CSS.supports("font-weight", "initial")) {
  // use it
}

Documentation (MDN)

Specification

Sub-features

Support for each part of the feature (8). The overall table above shows when the whole feature works.

Sub-featureChromeEdgeFirefoxSafariChrome AndroidFirefox AndroidSafari iOS
@font-face.font-weight4123.53.11842
font-weight212111841
font-weight.bold212111841
font-weight.bolder212111841
font-weight.lighter212111841
font-weight.normal212111841
font-weight.number62176111626111
svg.global_attributes.font-weight212111841