What is a PEF file?
PEF stands for Pentax Electronic File. It was created by Pentax and first released in 2003. PEF is the raw format of Pentax DSLRs since the *ist D in 2003. Most Pentax bodies can save DNG instead, a choice in the camera menu, so a Pentax shooter may have raw photos in either format.
| Type | image |
|---|---|
| Compression | Lossless |
| Colour | raw sensor data, usually 12 or 14 bits per pixel |
| Transparency | No |
| Animation | No |
| In a browser | does not open in browsers; macOS Photos and Preview, Lightroom and darktable open it |
| Common uses | Pentax DSLRs since the *ist D |
| MIME type | image/x-pentax-pef |
Which format should you convert PEF to?
- PEF to PDF to print, or to attach as a document.
PEF is lossless, so converting it to a lossy format is where the file gets much smaller.
How to open a PEF file
A PEF file does not open in a web browser, but most photo apps read it. Here is what works on each device.
| Windows | The Photos app opens it with Microsoft's free Raw Image Extension; Lightroom and darktable (free) edit it. |
|---|---|
| Mac | Photos and Preview open it; Lightroom and darktable edit it. |
| iPhone and iPad | The Files app previews it and Photos opens it once imported; Lightroom Mobile edits it. |
| Android | Few Android apps read PEF. Convert it to JPG here to view it anywhere. |
Want the technical details? See what a .pef file is, with its MIME type, file signature and a viewer.
PEF compared with other image formats
How PEF stacks up against the formats people most often convert it to or from:
| Format | Compression | Transparency | Released | Best for |
|---|---|---|---|---|
| PEF | Lossless | No | 2003 | Pentax DSLRs since the *ist D |
| JPG | Lossy | No | 1992 | camera photos, web images and email attachments |
| PNG | Lossless | Yes | 1996 | screenshots, logos, diagrams and anything with transparency |
| WebP | Either | Yes | 2010 | images served by websites to save bandwidth |
| HEIC | Lossy | Yes | 2017 | photos taken on iPhones and iPads since iOS 11 |
How to use the PEF converter
- Choose the format you want in the Convert to menu.
- Drop your PEF files on the box, or press Choose PEF files. Several files can go in at once.
- Adjust the settings if you need to; the defaults suit most people.
- Press Convert and save each file with its Download button. The file is converted on our server and deleted as soon as the result is sent back.
Tips for converting PEF files without losing quality
PEF is lossless, so it is a good source for any conversion. Converting it to a lossy format is where the file gets much smaller, and converting it to another lossless format keeps every pixel.
- Keep the raw file. It holds the full sensor data, with far more room for adjusting exposure and colour than any JPG or PNG made from it.
- Choose JPG to share or upload a photo, and PNG or TIFF when the picture will be edited further, since they add no compression loss.
- The conversion is a neutral development with the white balance the camera recorded. For an edited look, develop the file in Lightroom, darktable or RawTherapee instead.
- The server accepts files up to 25 MB, which fits the raw files of most cameras; very high-resolution cameras can go past it.
Convert PEF files from the command line
LibRaw and ImageMagick do the same on your own computer:
dcraw_emu -w -o 1 -q 3 -T input.pef
magick input.pef.tiff output.pdfConverting on your own computer keeps the file entirely local, which is worth it for very large or very sensitive documents. For everything else, the converter on this page does it without installing anything.
PEF converter FAQ
What is a PEF file?
PEF stands for Pentax Electronic File, an image format created by Pentax in 2003. PEF is the raw format of Pentax DSLRs since the *ist D in 2003. Most Pentax bodies can save DNG instead, a choice in the camera menu, so a Pentax shooter may have raw photos in either format.
How do I open a PEF file?
PEF does not open in browsers; macOS Photos and Preview, Lightroom and darktable open it. If the program you need will not open it, convert it to a more widely supported format above.
What is the most common PEF conversion?
PEF to PDF is the conversion people search for most. The PEF is developed by LibRaw, the open-source camera RAW decoder, on our conversion server: the sensor data is turned into a full-colour picture with the white balance the camera recorded, AHD demosaicing and standard sRGB colour.
Does converting PEF files here upload them?
Yes. PEF conversions need LibRaw and ImageMagick, open-source programs that cannot run in a browser, so they run on our conversion server. The file is uploaded, converted, and deleted together with the result as soon as the result has been sent back to you. Nothing is kept.
Is the PEF converter free?
Yes. There is no sign-up and no watermark. Conversions that use our server accept files up to 25 MB, with a fair-use limit per hour. The site is supported by advertising.
Can I convert PEF files on iPhone or Android?
Yes. Open this page in Safari on iPhone and iPad, or in Chrome on Android, choose your PEF files and download the results to your Downloads folder.
Can I convert several PEF files at once?
Yes. Drop as many as you like; they are converted one after another, each with its own download button.