TTF vs OTF vs WOFF vs WOFF2

Desktop formats

TTF and OTF are installable formats used by operating systems and design applications. Either can contain high-quality outlines and OpenType features. The extension alone does not tell you whether one font is better drawn or more complete than another.

Web formats

WOFF and WOFF2 package fonts for delivery through a website. WOFF2 normally produces smaller files and is the preferred modern format. A webfont licence is still required; converting a desktop font does not create permission to embed it online.

• TTF: common desktop compatibility
• OTF: desktop format with OpenType capabilities
• WOFF2: preferred modern web delivery
• WOFF: legacy web fallback

Avoid unnecessary conversion

Conversion can remove metadata, hinting, colour information or layout features if the tool is unsuitable. Download an authorised web package from the official source whenever possible and verify the resulting file before publication.

What the extension does and does not tell you

TTF and OTF describe containers used by desktop software; they do not provide a reliable quality ranking. An OTF file can contain PostScript-style outlines, while OpenType layout features can also appear in a TTF-flavoured file. Kerning, hinting, language coverage and drawing quality must be inspected in the actual font rather than inferred from the filename.

WOFF and WOFF2 are compressed web-delivery containers. They are not a licence workaround and should not normally be installed as the editable desktop master. Keep authorised source files separate from generated web assets, and preserve names and metadata so browsers select the intended family and style.

Choose a format by destination

For a design workstation, install the authorised TTF or OTF supplied by the foundry. For a modern website, use an authorised WOFF2 subset or package and declare weight and style accurately in each @font-face rule. For an app, game, e-book or document, the important question is whether the licence permits that form of embedding, not which extension is easiest to copy.

After conversion or subsetting, test accented text, punctuation, variable axes and OpenType features. Compare the new file with the source and keep automated tools out of the workflow when the licence forbids modification.

• Desktop design: authorised TTF or OTF.
• Modern web delivery: usually WOFF2.
• Legacy web support: add WOFF only when evidence requires it.
• Apps and documents: verify embedding rights before packaging.