JPG to PGM converter
Convert JPG to PGM in seconds, free and unlimited. No upload, no sign-up, no watermark: your image never leaves your device.
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Quick answer: To convert JPG to PGM, add the JPG file to the iHateFiles JPG to PGM converter and press Convert. The conversion runs in your browser, so the file is never uploaded, and it is free with no sign-up, watermark or size limit. PGM is lossless, so nothing degrades further, though the damage JPG already did cannot be undone.
Should you convert JPG to PGM?
Do this when you are about to edit the file and want no further loss. Do not do it hoping to improve a JPG: PGM preserves what it is given, including the damage.
JPG is lossy and PGM is not
Moving from JPG to PGM stops any further loss, but it cannot undo what JPG already discarded: that detail was thrown away when the file was first written and is not in it any more. Expect the PGM to be considerably larger while looking exactly the same, because it is now storing the JPG artefacts faithfully too.
PGM reduces the colour first
Before PGM compresses anything it reduces the image to greyscale. Flat colour, logos and line art survive that easily. A photograph coming from JPG will band visibly, and no quality setting changes it, because the limit is the format rather than the encoder.
Expect a much larger file
PGM stores every pixel exactly, including the compression artefacts the JPG already has. The file will grow, sometimes by a factor of ten, without looking any better. Do this when you need to edit without further loss, not to improve the image.
JPG and PGM side by side
| JPG | PGM | |
|---|---|---|
| Compression | Lossy | Lossless |
| Transparency | No | No |
| Animation | No | No |
| Written here | Yes | Yes |
What usually goes wrong
About the JPG. Re-saving a JPG repeatedly degrades it every time, because it re-encodes from the already damaged version. Edit from the original, and export to JPG once at the end.
About the PGM. Converting a colour image to PGM throws the colour away for good. Keep the original if you might want it back.
How to convert JPG to PGM
- Add your JPG file. It is read from your disk and stays there.
- Check the settings. The output format is already set to PGM.
- Press convert and the PGM file is saved back to your device.
Questions
How do I convert JPG to PGM?
Open this page, add your JPG file, and press convert. The file is decoded and re-encoded by your own browser and saved back to your device. Nothing is uploaded.
Is this JPG to PGM converter free?
Yes, completely. There is no account, no sign-in, no watermark and no daily limit, because there is no server doing the work. Your own device does it.
Are my files uploaded anywhere?
No. There is no upload endpoint. The conversion runs inside this browser tab, so your file never leaves your device. You can open your browser's network panel and watch: nothing carrying your file is sent.
Is there a file size limit?
No fixed limit. Because the work happens on your machine there is no server quota. The only ceiling is your own device's memory, which for video means very large files may be slow.
Will converting to PGM lose quality?
PGM compresses without loss, but it first reduces the image to greyscale, discarding all colour. Flat colour and line art come through unchanged; a photograph will band and lose subtlety.
Can I convert several JPG files at once?
Yes. Add as many as you like and they are converted one after another, then offered as a single ZIP.