The mask-position CSS property sets the initial position, relative to the mask position layer set by mask-origin, for each defined mask image.

/* Keyword values */
mask-position: top;
mask-position: bottom;
mask-position: left;
mask-position: right;
mask-position: center;

/* <position> values */
mask-position: 25% 75%;
mask-position: 0px 0px;
mask-position: 10% 8em;

/* Multiple values */
mask-position: top right;
mask-position: 1rem 1rem, center;

/* Global values */
mask-position: inherit;
mask-position: initial;
mask-position: unset;


One or more <position> values, separated by commas.


One to four values representing a 2D position regarding the edges of the element's box. Relative or absolute offsets can be given. Note that the position can be set outside of the element's box.

Formal definition

Initial valuecenter
Applies toall elements; In SVG, it applies to container elements excluding the defs element and all graphics elements
Percentagesrefer to size of mask painting area minus size of mask layer image (see the text for background-position)
Computed valueConsists of two keywords representing the origin and two offsets from that origin, each given as an absolute length (if given a <length>), otherwise as a percentage.
Animation typerepeatable list of simple list of length, percentage, or calc

Formal syntax

<position>#where <position> = [ [ left | center | right ] || [ top | center | bottom ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ]? | [ [ left | right ] <length-percentage> ] && [ [ top | bottom ] <length-percentage> ] ]where <length-percentage> = <length> | <percentage>


Setting mask position


#wrapper {
  border: 1px solid black;
  width: 250px;
  height: 250px;

#masked {
  width: 250px;
  height: 250px;
  background: blue linear-gradient(red, blue);
  mask-image: url(;
  mask-repeat: no-repeat;
  mask-position: top right; /* Can be changed in the live sample */
  margin-bottom: 10px;



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

Browser compatibility

BCD tables only load in the browser

See also