.WOFF File Extension

Web font file created in the WOFF (Web Open Font Format) format, an open format used for delivering webpage fonts on the fly; saved as a compressed container and supports TrueType (.TTF) and OpenType (.OTF) fonts; also supports font licensing information.

WOFF files allow Web developers to use custom fonts rather than the standard Web fonts. Many browsers support the WOFF format, but most of them do not support WOFF files until recent versions.

NOTE: WOFF files are referenced within CSS files using the @font-face rule.