coderef

Case-insensitive attribute selectorBaseline · Widely available

The i identifier in a CSS attribute selector matches attribute values case-insensitively in document languages like XML where attribute values are case-sensitive.

Supported in all major browsers for at least 30 months — safe to use without fallbacks. Baseline since Jan 15, 2020. Widely available since Jul 15, 2022.

How to use ↓Compare browsers

Browser support

DesktopChrome
1–48Not supported
49+Supportedsince Mar 2, 2016
Current: 155
Edge
12–18Not supported
79+Supportedsince Jan 15, 2020
Current: 154
Firefox
1–46Not supported
47+Supportedsince Jun 7, 2016
Current: 157
Safari
1–8Not supported
9+Supportedsince Sep 30, 2015
Current: 27
MobileChrome Android
18–48Not supported
49+Supportedsince Mar 9, 2016
Current: 155
Firefox Android
4–46Not supported
47+Supportedsince Jun 7, 2016
Current: 157
Safari iOS
1–8Not supported
9+Supportedsince Sep 16, 2015
Current: 27

How to use

This feature is Baseline widely available — use it freely, no fallback needed.

Example

Full syntax and examples are on MDN — see the links below.

Feature detection

CSS · check before using
@supports selector(:attribute) {
  /* styles that use :attribute */
}

/* or in JavaScript */
if (CSS.supports("selector(:attribute)")) {
  // use it
}

Specification

Usage share