EOT File Format (.eot)
An EOT file wraps a subsetted, compressed OpenType or TrueType font in a proprietary container that only Internet Explorer's @font-face implementation ever read.
EOT at a glance#
| Full name | Embedded OpenType |
|---|---|
| File extension | .eot |
| Category | Fonts |
| Developer | Microsoft |
| MIME types | application/vnd.ms-fontobject |
| Compression | Lossless |
| Specification | Embedded OpenType File Format (W3C Submission) |
| FileFlip support | FileFlip reads and writes this format |
What a .eot file can hold#
These are the things a EOT file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.
| Embedded metadata | Yes |
|---|---|
| Encryption | Yes |
Strengths and limitations of EOT#
What EOT does well
- Subsetting could strip a font down to only the characters a page actually used, shrinking it further than compression alone
- A root string could domain-lock a font, letting a foundry restrict which websites were licensed to embed it
Where EOT falls short
- Internet Explorer was the only browser that ever implemented it; Edge never added support
- The W3C declined to standardize Microsoft's EOT submission and recommended WOFF instead
- No modern tooling actively maintains EOT support, so producing one today only serves legacy Internet Explorer targets
There's no current reason to choose EOT; it only ever mattered for Internet Explorer 6 through 8, both long unsupported.
Convert away from EOT to WOFF2 and TTF for any website still shipping it, since no browser in current use reads EOT at all.
How to open a .eot file#
A .eot file opens in the programs below, grouped by the platform you are on. If you would rather not install anything, FileFlip converts EOT into a format your machine already opens, and it does it in the browser tab rather than on a server.
| Platform | Programs that open it |
|---|---|
| Windows | FontForge |
| Web | FileFlip |
EOT questions people ask#
Do any current browsers support EOT fonts?
No. EOT only ever worked in Internet Explorer, and Microsoft Edge, IE's replacement, never implemented support for it. Every browser in current use needs WOFF, WOFF2, TTF or OTF instead.
What was EOT's domain-locking feature for?
EOT could embed a root string listing the domains a font was licensed to appear on, and Internet Explorer would refuse to render the font on any other domain. Font foundries liked that it discouraged casual copying, but no other browser vendor implemented the check, which was part of why EOT never became a cross-browser standard.
Why would I still need to convert a file to EOT today?
Only if a website deliberately still supports Internet Explorer 6 through 8, which is rare given that Microsoft ended support for those browsers years ago. Any current @font-face declaration can drop the EOT source entirely and rely on WOFF2 with a WOFF fallback.
Converting EOT files#
Convert EOT to another format
Convert another format to EOT
Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.