flood-opacity

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

Note: As a presentation attribute, flood-opacity can be used as a CSS property.

As a presentation attribute, it can be applied to any element but it has effect only on the following two elements: <feFlood> and <feDropShadow>

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

<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" style="filter: url(#flood1);" />
  <rect x="0" y="0" width="200" height="200" style="filter: url(#flood2); transform: translateX(220px);" />
</svg>

Usage notes

<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

Browser compatibility

See also

• flood-color