What happens when you convert TTF to OTF
- FontForge, the open-source font editor, reads the TTF on our conversion server and writes it as an OTF font.
- If the font has TrueType (quadratic) outlines, FontForge redraws them as PostScript (cubic) curves in a CFF table, the usual content of an .otf. The shapes are the same, but TrueType hinting is dropped, so small sizes on Windows may render a little differently.
- Double-click the result to install it on Windows or a Mac, provided the font's licence allows desktop use.
- This conversion runs on our server: the file is uploaded, converted, and deleted together with the result as soon as the result has been sent back to you. Nothing is kept. Files up to 25 MB are accepted.
How to convert TTF to OTF online
- Press "Choose TTF files" and select one or more files, or drag them onto the box. Files up to 25 MB each can be converted.
- There are no settings to choose: the converter keeps everything the target format can hold.
- Press "Convert to OTF". The file is uploaded to our conversion server, converted in a few seconds, and deleted together with the result as soon as the result is sent back.
- Save each OTF with its download button. Our server has already deleted both your TTF and the OTF by then.
Why convert TTF to OTF?
TTF files usually come from installing fonts on a computer and embedding them in documents. People convert them to OTF when a design program, print workflow or font tool expects PostScript (CFF) outlines, which is what an .otf file usually holds.
How to convert TTF to OTF on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your TTF files in from File Explorer, and press Convert. Each OTF is saved to your Downloads folder.
On a Mac
Safari, Chrome and Firefox all work. Drag the TTF files from Finder onto the drop zone and the OTF files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose TTF files. You can pick from Photos or from the Files app. The converted OTF appears in Files, in the Downloads folder.
On Android
Open the page in Chrome, tap Choose TTF files and pick them from Files or your gallery. The OTF is saved to the Download folder, where any file manager can find it.
Best settings for TTF to OTF
Font conversion has no quality settings: the outlines, metrics and names are carried over.
After converting, install the font and type a sample, including accented letters and numbers, to confirm it before you use it.
TTF vs OTF: the differences
| TTF | OTF | |
|---|---|---|
| Full name | TrueType font | OpenType font |
| Type | font | font |
| Created by | Apple | Microsoft and Adobe |
| First released | 1991 | 1996 |
| Compression | Lossless | Lossless |
| What it holds | glyph outlines drawn with quadratic curves | glyph outlines, usually cubic PostScript curves, plus typographic features |
| In a browser | installs on Windows, Mac and Linux; browsers load it through CSS | installs on Windows, Mac and Linux; browsers load it through CSS |
| Common uses | installing fonts on a computer and embedding them in documents | professional typography, ligatures and design work |
| MIME type | font/ttf | font/otf |
About TTF and OTF files
What is a TTF file?
TrueType was created by Apple and adopted by Microsoft, which is why every desktop system installs TTF fonts natively. The outlines are made of quadratic curves.
What is an OTF file?
OpenType extends TrueType with advanced typography such as ligatures and alternate glyphs. An .otf file usually holds PostScript-style cubic outlines rather than TrueType curves.
TTF to OTF not working? Common problems
- "Files up to 25 MB can be converted." Server conversions have a size limit. A font that large usually holds several scripts; subset it to the characters you need first.
- "The conversion took too long and was stopped." Very long or complex files can pass the 90 second limit. Split the file and convert the parts.
- "This file is not really in TTF format." The converter checks every file before it runs anything, so a file of another format renamed to .ttf is refused. Choose the page for its real format.
Convert TTF to OTF from the command line
FontForge does the same on your own computer:
fontforge -lang=py -c "import fontforge, sys; fontforge.open(sys.argv[1]).generate(sys.argv[2])" input.ttf output.otfConverting on your own computer keeps the file entirely local, which is worth it for very large or very sensitive documents. For everything else, the converter on this page does it without installing anything.
TTF to OTF converter FAQ
Will I lose quality converting TTF to OTF?
The glyphs look the same: outlines are converted between curve types with no visible difference. Hinting may change, which only shows at small sizes on Windows.
Why is the OTF a different size from the TTF?
The OTF can differ in size from the TTF by a fair amount, because the two outline types store curves differently.
Are my TTF files uploaded?
Yes, for this conversion. A faithful TTF to OTF conversion needs FontForge, the open-source font editor, which cannot run in a browser. The file travels over an encrypted connection, is converted in a private temporary folder, and is deleted together with the OTF as soon as the result has been sent back to you. We do not keep, read or share it.
Can I convert several TTF files to OTF at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open an OTF file?
OTF installs on Windows, Mac and Linux; browsers load it through CSS. OTF is common for professional typography, ligatures and design work.
Is this TTF to OTF converter free?
Yes. There is no sign-up and no watermark. Because this conversion uses our server, there is a fair-use limit of 25 MB per file and a number of files per hour, which stops the service being overloaded.
Can I convert TTF to OTF on my phone?
Yes. It works in Safari on iPhone and iPad and in Chrome on Android. The conversion happens on our server, so it is as fast on a phone as on a computer; the OTF is saved to your Downloads folder.