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css property

`font-synthesis-weight` CSS property

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The font-synthesis-weight CSS 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

/* 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

This property is specified as one of the following keyword 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

Formal syntax

Examples

Disabling synthesis of bold typeface

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

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

@import "https://fonts.googleapis.com/css2?family=Montserrat&display=swap";

.english {
  font-family: "Montserrat", sans-serif;
}
.no-syn {
  font-synthesis-weight: none;
}

Result

Interactive exampleOpen the canonical MDN source to run this embedded demo.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also