TTF and OTF are the two font file types you will meet most often. Both work on Windows and macOS and both display text cleanly. The difference is mostly under the hood.
TrueType (.ttf)
TrueType was developed by Apple and adopted widely across Windows. It is reliable, broadly compatible, and a safe default for everyday documents and most design work.
OpenType (.otf)
OpenType is the newer standard. It can store more characters and supports advanced typographic features such as alternate letterforms, ligatures, small caps and stylistic sets. If a font offers expressive extras, OpenType is usually how they are delivered.
Which should you choose
- For general use, either format is fine. Pick whichever your download provides.
- For advanced typography with alternates and ligatures, prefer OpenType.
- If an older program rejects one format, try the other.
License terms vary from one font to another. Always review the license included with a specific font before using it, especially for commercial work.