What is a PPM file?
PPM stands for Portable Pixmap. It was created by Jef Poskanzer (Netpbm) and first released in 1988. PPM is about as simple as an image format gets: a short header with the width, height and maximum value, then the red, green and blue value of every pixel, uncompressed. That makes it easy for programs to write and very large on disk.
| Type | image |
|---|---|
| Compression | Lossless |
| Colour | 8 or 16 bits per channel, RGB |
| Transparency | No |
| Animation | No |
| In a browser | does not open in browsers; GIMP, IrfanView and Photoshop open it |
| Common uses | output of scientific tools, camera and video software, and image-processing scripts |
| MIME type | image/x-portable-pixmap |
Which format should you convert PPM to?
- PPM to JPG for photos that must open everywhere and stay small.
- PPM to PNG for screenshots, logos and anything with transparency.
- PPM to PDF to print, or to attach as a document.
PPM is lossless, so converting it to a lossy format is where the file gets much smaller.
How to open a PPM file
A PPM file does not open in a web browser, and only some devices have a program for it. Here is what works on each. If none of these is to hand, converting the file to PNG here is the quickest way to see what is inside it.
| Windows | GIMP, IrfanView (both free) and Photoshop open it. |
|---|---|
| Mac | GIMP (free) and Photoshop open it. |
| iPhone and iPad | The Files app cannot show PPM. Convert it to PNG or JPG here to view it. |
| Android | Most gallery apps cannot show PPM. Convert it to PNG or JPG here to view it. |
Want the technical details? See what a .ppm file is, with its MIME type, file signature and a viewer.
PPM compared with other image formats
How PPM stacks up against the formats people most often convert it to or from:
| Format | Compression | Transparency | Released | Best for |
|---|---|---|---|---|
| PPM | Lossless | No | 1988 | output of scientific tools, camera and video software, and image-processing scripts |
| 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 PPM converter
- Choose the format you want in the Convert to menu.
- Drop your PPM files on the box, or press Choose PPM 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 PPM files without losing quality
PPM 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 original file. It holds the layers, masks or raw data that a converted image does not, and you can always convert from it again.
- Choose PNG for artwork, screenshots and anything with sharp edges, and JPG for photos that must be small.
- Converted images are flattened: layers, adjustments and editable text become pixels, so make changes in the original and convert again.
- The server accepts files up to 25 MB; save very large files at a smaller size first.
Convert PPM files from the command line
ImageMagick does the same on your own computer:
magick input.ppm -background white -flatten output.epsConverting 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.
PPM converter FAQ
What is a PPM file?
PPM stands for Portable Pixmap, an image format created by Jef Poskanzer (Netpbm) in 1988. PPM is about as simple as an image format gets: a short header with the width, height and maximum value, then the red, green and blue value of every pixel, uncompressed. That makes it easy for programs to write and very large on disk.
How do I open a PPM file?
PPM does not open in browsers; GIMP, IrfanView and Photoshop 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 PPM conversion?
PPM to EPS is the conversion people search for most. ImageMagick, the open-source image toolkit, reads the PPM on our conversion server and embeds it in an EPS.
Does converting PPM files here upload them?
Yes. PPM conversions need ImageMagick, an open-source program 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 PPM 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 PPM files on iPhone or Android?
Yes. Open this page in Safari on iPhone and iPad, or in Chrome on Android, choose your PPM files and download the results to your Downloads folder.
Can I convert several PPM files at once?
Yes. Drop as many as you like; they are converted one after another, each with its own download button.