Image
What is a .thn file?
A .thn file is a Graphic Workshop for Windows Thumbnail File. This is an image format — a picture, drawing or graphic.
How to open a .thn file
- GIMP (free) and IrfanView open a very wide range of image formats, including obsolete ones.
- XnView MP is the best bet for unusual or legacy image types.
- Your operating system's built-in viewer may work for mainstream formats.
The registry records this extension against Graphic Workshop for Windows Thumbnail File, so software from that family is the most likely match.
How to convert a .thn file
- Open it in GIMP or XnView and export as .png (lossless) or .jpg (smaller).
The technical record
For archivists, developers and the merely curious: these are the PRONOM registry entries for .thn.
| Format name | Version | MIME type | PUID |
|---|---|---|---|
| Graphic Workshop for Windows Thumbnail File | — | — | fmt/336 |