The Can I use... test suite


This is a basic test suite of various web technologies for the When Can I Use website.

It is used to quickly test basic support for features in upcoming browsers, rather than any full support of the feature's specification.

Results on this page generally match the results as they appear on the When Can I Use site, but may not always due to a variety of circumstances (test may pass but support is actually buggy, not tested well enough, has alternative method, etc).

Four different types of tests are used:

Automated JS-based tests. (m) means Modernizr is used.
Requires visual confirmation/comparison to confirm
Test must create a 30x30px green (lime) square
Requires interaction to confirm support

If you are interested in contributing tests, follow these instructions.

Show all features

Feature Unprefixed tests Prefixed tests

Srcset and sizes attributes

[Feat] [Tests]


Test for 'srcset' in document.createElement('img')


Test for 'sizes' in document.createElement('img')


Test if "sizes" works as expected
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