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@charset

files/en-us/web/css/reference/at-rules/@charset/index.md

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The @charset CSS rule specifies the character encoding used in the style sheet. This syntax is useful when using non-{{Glossary("ASCII")}} characters in some CSS properties, like {{ cssxref("content") }}. Although the first character in @charset is the @ symbol, it is not an at-rule. It is a specific byte sequence that can only be placed at the very beginning of a stylesheet. No other characters, except the Unicode byte-order mark, are allowed before it. It also does not follow normal CSS syntax rules such as use of quotes or whitespace.

If a @charset is not recognized as the charset declaration, it is parsed as a normal at-rule. The CSS syntax module deprecates this fallback behavior, defining it as an unrecognized legacy rule to be dropped when a stylesheet is grammar-checked.

As there are several ways to define the character encoding of a style sheet, the browser will try the following methods in the following order (and stop as soon as one yields a result):

  1. The value of the Unicode byte-order character placed at the beginning of the file.
  2. The value given by the charset attribute of the Content-Type: HTTP header or the equivalent in the protocol used to serve the style sheet.
  3. The @charset CSS declaration.
  4. Use the character encoding defined by the referring document: the charset attribute of the {{ HTMLElement("link") }} element. This method is obsolete and should not be used.
  5. Assume that the document is UTF-8.

Syntax

css
@charset "UTF-8";
@charset "iso-8859-15";

Parameters

  • charset
    • : A {{cssxref("<string>")}} denoting the character encoding to be used. It must be the name of a web-safe character encoding defined in the IANA-registry, and must be double-quoted, following exactly one space character (U+0020), and immediately terminated with a semicolon. If several names are associated with an encoding, only the one marked with preferred must be used.

Formal syntax

Note that the @charset rule is not parsed via syntax, but via a specific byte sequence of the following form:

plain
@charset "<charset>";

Examples

Valid and invalid charset declarations

css-nolint
@charset "UTF-8"; /* Set the encoding of the style sheet to Unicode UTF-8 */
css-nolint
@charset 'iso-8859-15'; /* Invalid, wrong quotes used */
@charset  "UTF-8"; /* Invalid, more than one space */
 @charset "UTF-8"; /* Invalid, there is a character (a space) before the declarations */
@charset UTF-8; /* Invalid, the charset is a CSS <string> and requires double-quotes */

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also