How to convert PNM to PNG
To convert PNM to PNG, upload your PNM file, choose PNG as the output format and press Convert. The finished PNG file is ready to save to your phone or computer in seconds, free, with no watermark and no sign-up. Your file is deleted from our server about 30 minutes after the conversion.
This free online converter changes PNM images into PNG files in seconds, with no software to install and no watermark. You can convert several files at once, resize them and choose the quality for formats that support it. Metadata such as location tags is removed from the output for privacy.
Reasons to switch from PNM to PNG
- Lossless, so no quality loss
- Full alpha transparency
- Sharp text and edges
- Works with: every browser, editor and operating system
What to expect from this conversion
- Both formats store the pixels without loss, so the picture stays identical. Only the file size and compatibility change.
PNM vs PNG
| Property | PNM | PNG |
|---|---|---|
| Full name | Portable Anymap | Portable Network Graphics |
| Released | 1988, Jef Poskanzer (Netpbm) | 1996, PNG Development Group / W3C |
| Compression | None (uncompressed) | Lossless |
| Transparency | No | Yes |
| Animation | No | No |
| Bit depth | 1, 8 or 16-bit | 8-bit or 16-bit |
| Shown in browsers | No | Yes |
| Best for | Unix-style image pipelines; teaching and research | screenshots and UI graphics; logos with transparent backgrounds |
Steps to convert PNM to PNG
- Drop your PNM image file onto the converter, or click to choose it.
- Check that PNG is selected as the target and adjust the options if you want.
- Press Convert, then download your new PNG file when it finishes.
Tips for the best result
- Use quality 80 to 90 for photos: it is visually close to the original at a much smaller size.
- Set a width if the image will be shown on a small screen, which also reduces the file size.
- Choose a background colour before converting transparent images to a format without transparency.
Frequently asked questions
How do I convert PNM to PNG?
Drop your PNM files on the converter, confirm that PNG is the target and press Convert. Download each file or the whole batch as a ZIP.
Is the PNM to PNG converter free?
Yes. It is free with no watermark, no sign-up and no limit on how many images you convert. The site is supported by ads.
Does converting PNM to PNG reduce quality?
Both formats store the pixels without loss, so the picture stays identical. Only the file size and compatibility change. The quality slider only affects formats that use lossy compression.
Will transparency be kept when I convert PNM to PNG?
PNM images do not contain transparency, so there is nothing to lose. PNG supports it if you edit the image later.
Which programs open PNG files?
PNG files open in every browser, editor and operating system.
How many images can I convert at once?
Up to 20 images per batch, each up to 60 MB. Files are deleted from the server about 30 minutes after conversion.