This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.


The ::-ms-fill CSS pseudo-element represents the filled-in portion of a <progress> element. This pseudo-element is non-standard and specific to Internet Explorer 10+, hence the vendor prefix.


Not part of any specification. Microsoft has a description on MSDN.


Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support Not supported Not supported 10.0 Not supported Not supported
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support Not supported Not supported ? Not supported Not supported

See also

Document Tags and Contributors

 Contributors to this page: cvrebert, Rupshree, teoli, jswisher, mrenty, Sebastianz
 Last updated by: cvrebert,