fill-opacity

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨March 2020⁩.

The fill-opacity attribute is a presentation attribute defining the opacity of the paint server (color, gradient, pattern, etc.) applied to a shape.

Note: As a presentation attribute, fill-opacity also has a CSS property counterpart: fill-opacity. When both are specified, the CSS property takes priority.

You can use this attribute with the following SVG elements:

Example

html,
body,
svg {
  height: 100%;
}

html

<svg viewBox="0 0 400 100" xmlns="http://www.w3.org/2000/svg">
  <!-- Default fill opacity: 1 -->
  <circle cx="50" cy="50" r="40" />

  <!-- Fill opacity as a number -->
  <circle cx="150" cy="50" r="40" fill-opacity="0.7" />

  <!-- Fill opacity as a percentage -->
  <circle cx="250" cy="50" r="40" fill-opacity="50%" />

  <!-- Fill opacity as a CSS property -->
  <circle cx="350" cy="50" r="40" style="fill-opacity: .25;" />
</svg>

Usage notes

Value	`[0-1]` \| <percentage>
Default value	`1`
Animatable	Yes

Note: SVG2 introduces percentage values for fill-opacity, however, it is not widely supported yet (See Browser compatibility below) as a consequence, it is best practices to set opacity with a value in the range [0-1].