What is a .raw file?
Camera RAW image · Image · Camera makers (Canon, Nikon, Sony, Adobe) · 1990s onward
RAW is not one format but a family of camera files that store the sensor's unprocessed data. That gives photographers huge latitude to adjust exposure and colour later, at the cost of large files and the need for editing software.
What is a .raw file used for?
A RAW file is the digital equivalent of a film negative. It records what the sensor captured before the camera applied sharpening, white balance or compression, so nearly everything can be changed afterward without loss.
Each maker uses its own variant, so Canon shoots CR2 or CR3, Nikon shoots NEF and Sony shoots ARW. Adobe's DNG is an open RAW format meant to work across brands.
Because RAW is unprocessed, you develop it in software like Lightroom, Capture One or the free darktable, then export a JPG or TIFF.
How to open a .raw file
The .raw format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list. For a step-by-step walkthrough, see how to open a .raw file.
Windows
- Lightroom
- darktable
- RawTherapee
- Photos (with codec)
macOS
- Photos
- Lightroom
- Preview
- Capture One
Linux
- darktable
- RawTherapee
- GIMP
Web
- Convert to JPG or TIFF first
How to convert a .raw file
You can convert a .raw file to JPG, TIFF, PNG, DNG using a conversion tool or the export menu of an app that opens it.
.raw file signature (magic bytes)
Programs recognise a .raw file by the bytes at the start of the file, not by its name. These are the signatures for RAW.
| Hex signature | Offset | Note |
|---|---|---|
| 49 49 2A 00 | 0 | TIFF-based RAW (CR2, NEF, DNG) |
| 4D 4D 00 2A | 0 | big-endian TIFF-based RAW |
See the full magic-numbers reference for every format.
Frequently asked questions
What is a .raw file?
RAW is not one format but a family of camera files that store the sensor's unprocessed data. That gives photographers huge latitude to adjust exposure and colour later, at the cost of large files and the need for editing software.
Why can't I open my camera RAW file?
Your viewer may not have the codec for that camera model. Use Lightroom, RawTherapee or darktable, or convert the file to DNG or JPG.