OTFOpenType Font
The OpenType font format, created by Microsoft and Adobe. It supports advanced typography such as ligatures and alternate glyphs.
Convert OTF to WOFF
Turn your OTF fonts into WOFF fonts in seconds. Conversion happens in your browser, so your files are never uploaded to a server.
- Files never uploaded
- Free, no sign-up
- No queue
OTF4F54544F000A0080
WOFF774F464600010000
The first bytes of a file often reveal its real format.
or drop them here. You can also paste an image (Ctrl+V).
Free · No sign-up · No upload
Files
These sample files are generated on the page. Convert them to try it out, or add your own.
How to convert OTF to WOFF
- 01
Add your OTF files
Click “Choose OTF files” or drop them on the page. You can add several at once.
- 02
Check the WOFF format
WOFF is already selected. The font flavour (TrueType or OpenType) is handled automatically.
- 03
Convert and download
Click “Convert”, then download your WOFF file. With several files, grab everything at once as a ZIP.
OTF to WOFF: what to know
Foundries often supply their fonts as OTF, with advanced typographic features: ligatures, small caps, old-style figures, stylistic sets. Converting to WOFF compresses each table without removing anything, so those features, the kerning and the full character set all remain available on your site. Nothing is trimmed to save weight either: a very complete font will still give a sizeable WOFF.
Each style in a family is a separate file: Regular, Italic, Bold or Light are converted one at a time, then each is declared in its own @font-face block with the right weight and style. Only host the styles you actually use, as every file adds to the page’s loading time. Finally, check that your licence covers web use, which a desktop licence does not always include.
OTF vs WOFF: what’s the difference?
WOFFWeb Open Font Format
The web font format recommended by the W3C. It is a compressed TTF or OTF font that loads faster on a website.
OTF to WOFF: frequently asked questions
Is my OTF font turned into TrueType inside the WOFF?
No. The WOFF keeps the original outline type: an OTF with PostScript (CFF) outlines gives a CFF-based WOFF, and an OTF with TrueType outlines stays TrueType. Current browsers display both without trouble. Converting a CFF-based WOFF back later will indeed give you an .otf file again.
How do I turn on the ligatures and small caps of an OTF font on the web?
OpenType features survive in the WOFF; you just need to call them in CSS. Standard ligatures are on by default. Use font-variant-caps: small-caps for small capitals, font-variant-numeric: oldstyle-nums for old-style figures, and font-feature-settings for the rest, for example ss01 for the first stylistic set.
Are my OTF files uploaded to the internet?
No. The file is read and converted by your browser, on your device. Nothing is sent to a server, and nothing is kept after you close the page.
Does converting OTF to WOFF reduce quality?
No. The font tables are just compressed (WOFF) or decompressed (TTF, OTF), so the glyphs stay identical.
How many OTF files can I convert?
As many as you like, for free and without signing up. Add them all, then download the results one by one or in a single ZIP. The maximum size depends on your device and browser, with a few caps that protect its memory (for example 20,000 files per archive or 5 million filled cells per workbook: see the home page FAQ); a file over one of them is not converted, and a message says so.
Does it work on iPhone and Android?
Formatomat is designed for recent browsers on computers, iPhone and Android, with no app to install. A conversion the browser cannot do (a format it cannot read or write) is refused with a message that says so.