This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The mask-composite CSS property represents a compositing operation used on the current mask layer with the mask layers below it.

/* Keyword values */
mask-composite: add;
mask-composite: subtract;
mask-composite: intersect;
mask-composite: exclude;

/* Global values */
mask-composite: inherit;
mask-composite: initial;
mask-composite: unset;
Initial value add
Applies to all elements; In SVG, it applies to container elements excluding the <defs> element and all graphics elements
Inherited no
Media visual
Computed value as specified
Animation type discrete
Canonical order per grammar


One or more of the keyword values listed below, separated by commas.


For the composition the current mask layer is referred to as source, while all layers below it are referred to as destination.

The source is placed over the destination.
The source is placed, where it falls outside of the destination.
The parts of source that overlap the destination, replace the destination.
The non-overlapping regions of source and destination are combined.

Formal syntax


<compositing-operator> = add | subtract | intersect | exclude



#masked {
  width: 100px;
  height: 100px;
  background-color: #8cffa0;
  mask-image: url(https://mdn.mozillademos.org/files/12668/MDN.svg),
  mask-size: 100% 100%;
  mask-composite: add; /* Can be changed in the live sample */


Specification Status Comment
CSS Masking Module Level 1
The definition of 'mask-composite' in that specification.
Candidate Recommendation Initial definition

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support No1 ? 53 No No1 No1
Feature Android webview Chrome for Android Edge mobile Firefox for Android IE mobile Opera Android iOS Safari
Basic support ? ? ? 53 No ? ?

1. See also -webkit-mask-composite for a similar non-standard property that uses different keywords.

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