.woff
Font
WOFF (Web Open Font Format)
WOFF is a web font format that wraps TrueType or OpenType fonts with compression and metadata for efficient web delivery. WOFF reduces font file sizes by 40-60% compared to raw TTF/OTF, and it is supported by all modern browsers.
MIME Type
font/woff
Type
Binary
Compression
Lossless
Advantages
- + 40-60% smaller than raw TTF/OTF files
- + Supported by all modern browsers (IE9+)
- + Preserves all font features from the original TTF/OTF
Disadvantages
- − Larger than WOFF2 (Brotli compression is ~30% better than zlib)
- − Being superseded by WOFF2 for modern web use
- − Not suitable for desktop installation — web only
When to Use .WOFF
Use WOFF as a fallback for older browsers; prefer WOFF2 for modern browsers due to its superior compression.
Technical Details
WOFF files wrap sfnt font data (TTF or CFF) with zlib (DEFLATE) compression per table, a WOFF header, and optional private and extended metadata in XML format.
History
The W3C published WOFF 1.0 in 2012 as a recommendation for web fonts. It was developed collaboratively by Mozilla, Opera, and Microsoft to provide a standardized compressed font format for the web.