Add your PGM file
Drop one or more .pgm files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Converting a .pgm image to .avif re-encodes the pixels for a different balance of size, quality, and support. Free, private, and validated — the file never leaves your browser.
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.Converting a .pgm image to .avif re-encodes the pixels for a different balance of size, quality, and support. A .pgm file is a Portable Graymap: a single-channel greyscale image storing one intensity value per pixel, with the maximum value declared in the header. It is the middle rung of the Netpbm ladder — richer than a one-bit bitmap, simpler than a colour pixmap.
An .avif file stores a still image (or sequence) coded with the AV1 video codec inside a HEIF-derived container. It is currently among the most efficient image formats deployed on the web, routinely beating JPEG by half at similar quality while adding HDR, wide gamut, and alpha. For this route the practical draw is best-in-class compression among widely supported web formats and 10/12-bit HDR and wide-gamut color, which JPEG cannot represent — balanced against encoding is much slower than JPEG or WebP, especially at high effort settings, which is worth knowing before you commit a large batch.
The practical trigger for this conversion is usually a mismatch: with .pgm, uncompressed, so files are large relative to PNG for the same data. Switching to .avif buys you best-in-class compression among widely supported web formats, which is why it is the better fit for serving hero images and photo galleries where bandwidth savings are significant. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
| Aspect | Portable graymap (.pgm) | AVIF image (.avif) |
|---|---|---|
| Format type | Lossless — every pixel or sample is preserved exactly | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | p2 stores samples as whitespace-separated ASCII integers; P5 stores them as raw bytes | encodes AV1 intra frames; both lossy and a mathematically lossless mode are defined |
| Strongest at | machine vision and image-processing pipelines that operate on intensity alone | serving hero images and photo galleries where bandwidth savings are significant |
| Weak spot | uncompressed, so files are large relative to PNG for the same data | encoding is much slower than JPEG or WebP, especially at high effort settings |
| Metadata | none beyond header comments. No colour profile, no EXIF, no acquisition metadata — anything an instrument recorded alongside the pixels has to travel in a separate file | eXIF and XMP are stored as metadata items in the HEIF container alongside ICC profiles or CICP color signaling, and mainstream encoders preserve them on conversion |
Drop one or more .pgm files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Select .avif in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if AVIF is selectable, the route is real and validated.
Press Convert. Decoding and re-encoding happen on your device using the browser's native image pipeline and hand-tuned encoders.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid AVIF file. Outputs keep the original filename with the .avif extension.
Some. Since pgm is lossless-oriented and avif is lossy-oriented, the encoder will discard detail it judges least visible; the quality slider controls how aggressive that is. Keep the original .pgm if you may need a pristine master later.
Yes — the .pgm file is processed inside your browser tab and never uploaded. Decoding and re-encoding happen on your device using the browser's native image pipeline and hand-tuned encoders. Close the tab and the file is gone from memory.
Chrome 85+ (2020), Firefox 93+ (2021), and Safari 16+ (2022) render AVIF natively, covering the overwhelming majority of current browsers. On the desktop, macOS 13+ and Windows (via the AV1 Video Extension) preview it, but plenty of older editing and printing software cannot open it yet.
Smaller, usually dramatically so — that is the main reason this route exists. The quality slider trades size against fidelity; the default sits at the point where most people cannot spot the difference.
In .pgm, none beyond header comments. No colour profile, no EXIF, no acquisition metadata — anything an instrument recorded alongside the pixels has to travel in a separate file. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .pgm → .avif → .pgm is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.