PBM Converter
FileFlip converts PBM files into 61 other formats entirely inside your browser, using ImageMagick, MuPDF and Pandoc compiled to WebAssembly. The PBM file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert a PBM file?#
- Drop your PBM file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert PBM files online?#
Yes, because nothing is uploaded. FileFlip converts PBM files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What happens to a PBM file#
FileFlip converts PBM into 61 formats with ImageMagick, MuPDF and Pandoc, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | Image Files |
|---|---|
| File extension | .pbm |
| FileFlip support | Read and written |
| Conversions available | 61 |
| Engines | ImageMagick, MuPDF and Pandoc |
| Downloaded to your browser | 14.1 MB on the first conversion, then cached |
What is a PBM file?#
A PBM file stores a strictly black-and-white, one-bit-per-pixel raster image as plain ASCII characters or packed binary bits, in the Netpbm project's Portable Bitmap format.
Use PBM for a strictly black-and-white bitmap, such as a fax page or a stencil mask, that needs to move between tools without any image library.
Convert PBM to PNG once the image needs compression or has to sit alongside greyscale or colour images in the same pipeline.
The PBM file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
PBM questions people ask#
What does PBM stand for?
PBM stands for Portable Bitmap, the black-and-white member of the Netpbm family of image formats that Jef Poskanzer created to move images between Unix tools. It is the strictly one-bit sibling of the colour PPM and greyscale PGM formats.
Is a 1 a black pixel or a white pixel in a PBM file?
In a PBM file, a 1 represents a black pixel and a 0 represents a white pixel, which is the opposite of what many people expect from a plain greyscale scale. This is defined directly in the Netpbm project's own PBM specification.
Why is my PBM file bigger than a similar PNG?
A PBM file stores one bit per pixel with no compression at all, while PNG compresses that same data losslessly, so a large black-and-white image can end up many times smaller as a PNG. PBM trades file size for a format simple enough to read and write without any image library.