How to open a .otf file (Windows, Mac, Linux)

Q: Why can't I open my .otf file?

Usually your computer lacks an app that understands OTF. Install one of the apps listed here, or convert the file to a more common format.

A .otf file is a OpenType Font. If double-clicking does nothing, your computer simply does not have an app that reads OTF yet. Here is how to fix that on each operating system, using free software wherever possible.

Open a .otf file step by step

Confirm the file really is a .otf. Drop it into the WhatFileType file identifier, which reads its signature without uploading anything.
On Windows, open it with Windows Font Viewer or FontForge.
On Mac, use Font Book or FontForge.
On Linux, try Font viewer or FontForge.
Still stuck? Convert the .otf to TTF, which opens more widely.

Best apps to open .otf files

Windows

Windows Font Viewer
FontForge

macOS

Font Book
FontForge

Linux

Font viewer
FontForge

Web

Used via @font-face, prefer WOFF2

Before you open it: Generally safe. Install fonts from sources you trust.

Frequently asked questions

Why can't I open my .otf file?

Almost always because no installed app understands OTF. Install one of the apps above, or convert the file to a format your existing software already reads.

Should I use OTF or TTF?

For everyday use they are interchangeable. Choose OTF when the font offers advanced typography like ligatures and alternates that you want to use.