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 valueadd
Applies toall elements; In SVG, it applies to container elements excluding the <defs> element and all graphics elements
Computed valueas specified
Animation typediscrete
Canonical orderper 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(,
  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

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support No1 ?53 No No1 No1
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support ? ? ?53 ? ? No

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

Document Tags and Contributors

Contributors to this page: mfluehr, fscholz, wbamberg, Sebastianz, chrisdavidmills, teoli, Siilwyn
Last updated by: mfluehr,