How to open .TM files on Windows
To open .TM files on Windows, install GNU TeXmacs from the official TeXmacs website.
Step-by-step instructions
- Install GNU TeXmacs from the official TeXmacs website.
- In TeXmacs, use File → Open and select the .tm file (or right-click the file → Open with → GNU TeXmacs).
- If you only need to read it, ask the author to export from TeXmacs to PDF/HTML for easy viewing.
Common issues
The .TM file opens in the wrong program (or not at all)
This usually happens because the system has no TeXmacs association for .tm, or the file is not a TeXmacs document.
- Install GNU TeXmacs and open the file from inside TeXmacs (File → Open).
- Change the default app for .tm files to GNU TeXmacs (Windows/macOS/Linux file association settings).
- If TeXmacs cannot parse it, confirm with the sender what program created the file (since “.tm” can be used by unrelated software).
You’re on iOS/Android and can’t preview the file
Mobile operating systems generally do not include viewers for TeXmacs’ native .tm format.
- Open the file on a desktop (Windows/macOS/Linux) with GNU TeXmacs.
- Ask the author to export the document from TeXmacs to PDF/HTML for mobile viewing.
- If you must share it with others, prefer exporting to a common format rather than renaming the extension.
Text looks unreadable when opened in a plain text editor
.tm is TeXmacs’ structured document format and is not intended to be edited with generic text editors.
- Open the file in GNU TeXmacs for correct rendering and editing.
- Use TeXmacs’ export options if you need a plain-text or exchange-friendly format (for example, an XML-based export).
File appears corrupted or incomplete
Interrupted downloads/transfers or mismatched encodings can cause TeXmacs to fail when loading a document.
- Re-download or re-copy the file and try opening it again in GNU TeXmacs.
- Ask the sender to re-export or re-save the document from TeXmacs and resend it.
- If available, try opening a known-good .tm file to verify your TeXmacs installation is working.
Security note
Treat .tm files as untrusted input when received from unknown sources: like any complex document format, opening it requires parsing, and vulnerabilities in document parsers can exist.