font-synthesis-weight

Baseline 2023

Newly available

Since March 2023, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.

The font-synthesis-weightCSS property lets you specify whether or not the browser may synthesize the bold typeface when it is missing in a font family.

It is often convenient to use the shorthand property font-synthesis to control all typeface synthesis values.

Syntax

css

/* Keyword values */ font-synthesis-weight: auto; font-synthesis-weight: none; /* Global values */ font-synthesis-weight: inherit; font-synthesis-weight: initial; font-synthesis-weight: revert; font-synthesis-weight: revert-layer; font-synthesis-weight: unset;

Values

auto: Indicates that the missing bold typeface may be synthesized by the browser if needed.
none: Indicates that the synthesis of the missing bold typeface by the browser is not allowed.

Formal definition

Initial value	`auto`
Applies to	all elements and text. It also applies to `::first-letter` and `::first-line`.
Inherited	yes
Computed value	as specified
Animation type	discrete

Formal syntax

font-synthesis-weight = 
auto|
none

Examples

Disabling synthesis of bold typeface

This example shows turning off synthesis of the bold typeface by the browser in the Montserrat font.

HTML

html

<p class="english"> This is the default <strong>bold typeface</strong> and <em>oblique typeface</em>. </p> <p class="english no-syn"> The <strong>bold typeface</strong> is turned off here but not the <em>oblique typeface</em>. </p>

CSS

css

@import url("https://fonts.googleapis.com/css2?family=Montserrat&display=swap"); .english { font-family: "Montserrat", sans-serif; } .no-syn { font-synthesis-weight: none; }

Result

Specifications

Specification
CSS Fonts Module Level 4 # font-synthesis-weight