OTF Converter
FileFlip converts OTF files into 5 other formats entirely inside your browser, using the font engine compiled to WebAssembly. The OTF file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert an OTF file?#
- Drop your OTF file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert OTF files online?#
Yes, because nothing is uploaded. FileFlip converts OTF files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What happens to a OTF file#
FileFlip converts OTF into 5 formats with the font engine, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | Fonts |
|---|---|
| File extension | .otf |
| FileFlip support | Read only, so it is a source rather than a target |
| Conversions available | 5 |
| Engines | the font engine |
| Downloaded to your browser | 0.7 MB on the first conversion, then cached |
What is an OTF file?#
An OTF file stores a font's glyph outlines as PostScript-style cubic Bezier curves, along with the OpenType layout tables that drive ligatures and other typographic substitutions.
Use OTF for a font that relies on OpenType features like ligatures or stylistic alternates, which professional design and publishing software reads natively.
Convert OTF to WOFF2 before using it on a website, since browsers need a compressed web font format and OTF isn't one.
The OTF file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
OTF questions people ask#
What's the difference between OTF and TTF?
OTF adds an option for PostScript-style cubic Bezier outlines and OpenType's layout tables, like ligatures and language-specific substitutions, on top of the same font structure TTF uses. A TTF file can't hold those layout features; an OTF file can, whether its outlines are cubic or the same quadratic type TTF uses.
Can OTF fonts be converted back from other formats?
Not with every tool. Some font converters, including this one, can read an OTF file and write it out as TTF, WOFF or WOFF2, but can't write a new OTF file, because reconstructing CFF cubic outlines from a different source isn't supported by every font engine. Turning a WOFF or TTF file into a genuine OTF usually needs a dedicated font editor instead.
Does converting OTF to another format change its license?
No, and it doesn't grant new permissions either. A font's license governs how it can be used and distributed regardless of which container format it's stored in, so a font licensed for desktop use only doesn't become licensed for web embedding just because it was converted to WOFF2.