opacity

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

Theopacity attribute specifies the transparency of an object or of a group of objects, that is, the degree to which the background behind the element is overlaid.

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

You can use this attribute with the following SVG elements:

Unlikefill-opacity,stroke-opacity, andstop-opacity, which are applied to individual operations and are renderedwhen the element is rendered,opacity is applied to whole objects or groups, and is more like a post-processing operation on the rendered image of the object or group. Therefore, when you have bothopacity and the other opacity attributes in the same area, they will be overlaid on top of each other and cause the opacity to be multiplied.

Example

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

html

<svg viewBox="0 0 200 100" xmlns="http://www.w3.org/2000/svg">  <defs>    <linearGradient x1="0%" y1="0%" x2="0" y2="100%">      <stop offset="0%" stop-color="skyblue" />      <stop offset="100%" stop-color="seagreen" />    </linearGradient>  </defs>  <rect x="0" y="0" width="100%" height="100%" fill="url(#gradient)" />  <circle cx="50" cy="50" r="40" fill="black" />  <circle cx="150" cy="50" r="40" fill="black" opacity="0.3" /></svg>

Usage notes

Default value	`1`
Value	`<alpha-value>`
Animatable	Yes

<alpha-value>: The uniform opacity setting to be applied across an entire object, as a<number>. Any values outside the range 0.0 (fully transparent) to 1.0 (fully opaque) will be clamped to this range.