WOFF Format Guide & Converter

Web Open Font Format is Web Open Font Format 1.0 — a compressed font package for websites, introduced by Mozilla / W3C (2012). WOFF wraps TTF/OTF data with compression for CSS @font-face. Prefer WOFF2 today for smaller files, but WOFF remains a useful fallback in some pipelines.

Full name

Web Open Font Format

Kind

font

File extension

.woff

MIME type

font/woff

Developer / standard

Mozilla / W3C · 2012

Compression

zlib

Quality model

Lossless / not lossy

Container

No / single bitstream typical

Common codecs

—

Technical sources

—

Transparency

Not supported

Animation

No (still / non-animated typical use)

Typical size

Typically smaller than raw TTF/OTF

Browser support

Excellent

Compatibility

Works with CSS @font-face in browsers; not meant for OS font installation — keep TTF/OTF for desktop installs

WOFF compression: zlib. Lossless (or non-destructive packaging) keeps reconstructable data — size savings come from packing efficiency, not throwing detail away. Typical size profile: Typically smaller than raw TTF/OTF. Quality note: Lossless outlines with container compression

Quality: Lossless outlines with container compression

Typical size: Typically smaller than raw TTF/OTF

WOFF does not support an alpha channel. Convert to PNG, WebP, AVIF, or SVG when you need transparent backgrounds.

WOFF is a still-media or non-animated format in typical use. Use GIF, APNG, video, or animated WebP when you need motion.

Name tables, license/meta fields, and designer copyright strings live inside the font; web formats may include metadata blocks.

• Web font fallback stacks
• Older @font-face pipelines
• Licensed web embedding
• Converting desktop fonts for the browser

• Desktop OS font installation (use TTF/OTF)
• Ignoring font licenses
• Preferring WOFF over WOFF2 on modern-only sites
• App binary embedding without subsetting

• Built for the web
• Compressed vs raw TTF
• W3C lineage
• Works with @font-face

• Larger than WOFF2
• Not for OS install workflows
• License metadata still matters
• Obsolete as the primary modern choice

Works with CSS @font-face in browsers; not meant for OS font installation — keep TTF/OTF for desktop installs

Browsers: Excellent

• Format Convertly
• Web build tools

• Desktop and mobile browsers
• Modern desktops
• Phones and tablets with compatible apps

Load via CSS in a browser; inspect with font tools — not a double-click install font on most OS setups.

Convert between TTF, OTF, WOFF, and WOFF2 in Format Convertly for licensed web stacks, privately in-browser so font files never upload.

• Pick a target format from popular conversions or the full list below.
• Your file is read into browser memory — not uploaded to a server.
• Download the result when conversion finishes.

Incoming conversions strengthen the WOFF cluster — e.g. JPG → WOFF, PNG → WOFF.

Decision pages that cite WOFF — the next hop after a vs comparison.

Tools extend the format graph beyond one-off conversion — compression, metadata, and utilities for real workflows.

Uploading sensitive WOFF files to a random converter creates a third-party copy you cannot control. Format Convertly keeps processing on-device so photos, contracts, and exports stay private.