Image
What is a .nrrd file?
A .nrrd file is a Nearly Raw Raster Data (version 1). This is an image format — a picture, drawing or graphic. Confusingly, this extension has been used by 5 different formats over the years — they're all listed below.
This extension has been used by more than one format
5 different formats have claimed .nrrd over the years, so two files with the same extension aren't necessarily the same kind of thing.
How to open a .nrrd 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 Nearly Raw Raster Data, Nearly Raw Raster Data, Nearly Raw Raster Data and others, so software from that family is the most likely match.
How to convert a .nrrd 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 .nrrd.
| Format name | Version | MIME type | PUID |
|---|---|---|---|
| Nearly Raw Raster Data | 1 | — | fmt/1002 |
| Nearly Raw Raster Data | 2 | — | fmt/1003 |
| Nearly Raw Raster Data | 3 | — | fmt/1004 |
| Nearly Raw Raster Data | 4 | — | fmt/1005 |
| Nearly Raw Raster Data | 5 | — | fmt/1006 |