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flood-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.

The flood-opacity attribute indicates the opacity value to use across the current filter primitive subregion.

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

You can use this attribute with the following SVG elements:

Example

<svg viewBox="0 0 420 200" xmlns="http://www.w3.org/2000/svg">
  <filter id="flood1">
    <feFlood
      flood-color="seagreen"
      flood-opacity="1"
      x="0"
      y="0"
      width="200"
      height="200" />
  </filter>
  <filter id="flood2">
    <feFlood
      flood-color="seagreen"
      flood-opacity="0.3"
      x="0"
      y="0"
      width="200"
      height="200" />
  </filter>

  <rect x="0" y="0" width="200" height="200" filter="url(#flood1)" />
  <rect x="220" y="0" width="200" height="200" filter="url(#flood2)" />
</svg>

Usage notes

Value <alpha-value>
Initial value 1
Animatable Yes
<alpha-value>

A number or percentage indicating the opacity value to use across the current filter primitive subregion. A number of 0 or a percentage of 0% represents a fully transparent color, 1 or 100% represents a fully opaque color.

Specifications

Specification
Filter Effects Module Level 1>
# FloodOpacityProperty>

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
flood-opacity 5 12 3 15 6 18 4 14 6 1.0 4.4 6

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/SVG/Reference/Attribute/flood-opacity