Skip to main content


Attribute name must be lowercase.

Level: error

Config value

  1. true: enable rule
  2. false: disable rule
  3. ['fooBar', 'Test']: enable rule except for the given attribute names. All SVG camelCase properties are included, for example viewBox


"attr-lowercase": ['fooBar']

The following pattern is not considered a rule violation:

<img src="test.png" alt="test" />

<!-- known SVG attributes are ignored -->
<svg width="200" height="200" viewBox="0 0 200 200" />

The following pattern is considered a rule violation:

<img SRC="test.png" ALT="test" />