BMP to PFM Converter
Processing entirely on your device — large files may take a moment.
Bitmap Image and Portable Float Map exist for different jobs: BMP is Windows’ native uncompressed bitmap format. Every pixel is stored exactly as captured, which makes files large but trivially simple to read — common in older software and scanners. Convert PFM to PNG or JPG to get a viewable tone-mapped preview of float data.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How BMP compares to PFM
| BMP | PFM | |
|---|---|---|
| Compression | Usually none (RLE optional) | None (raw floats) |
| Transparency | Rarely (V5 header only) | Not supported |
| Animation | Not supported | Not supported |
| Metadata | Minimal | Minimal header only |
| Best for | Legacy software and scanner output | HDR interchange, render passes |
How to convert BMP to PFM
- 1
Select your files
Drag & drop your BMP files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to PFM". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted PFM file individually, or grab everything at once as a ZIP archive.
About the BMP format
BMP is Windows' native bitmap format, dating to 1990. It stores pixels essentially raw — rows of BGR values padded to 4-byte boundaries — with optional RLE compression that almost nobody uses. That simplicity is its whole personality: any program written since the dawn of Windows can read one in a dozen lines of code, which is why scanners and ancient lab software still emit it.
The cost of that simplicity is size: an uncompressed BMP of a photo runs dozens of times larger than a JPG. There is no meaningful metadata standard, transparency only exists via the rarely-implemented V5 header, and no modern workflow needs it. Treat BMP as a legacy interchange format you convert away from.
+Strengths
- ✓Zero compression artifacts — pixels stored as captured
- ✓Trivially easy to decode, even in ancient software
- ✓Universal inside the Windows world
!Limitations
- −Enormous files — dozens of times larger than JPG
- −No real metadata or color-management story
- −No role in modern web or print workflows
About the PFM format
PFM (Portable Float Map) stores pixels as raw 32-bit floating-point values — no palette, no compression tricks, just the numbers. It belongs to the Netpbm family (PBM/PGM/PPM) and is the lingua franca for handing high-dynamic-range data between renderers, tone-mapping experiments and radiance research scripts.
Because the values are floats, a PFM can hold sunlight and candlelight in the same image without clipping. Viewers rarely open it directly: convert to PNG or JPG to get a tone-mapped preview of the same data.
+Strengths
- ✓Full floating-point precision
- ✓Dead-simple text/binary layout
- ✓Widely read by research tooling
!Limitations
- −Enormous files (16 bytes per pixel)
- −Almost no viewer support
Why convert BMP to PFM?
Converting makes sense where the strengths of PFM meet what BMP cannot give you. Full floating-point precision Meanwhile Enormous files — dozens of times larger than JPG One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this BMP to PFM converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Will I lose quality converting BMP to PFM?
No — PFM is a lossless format, so every pixel of the converted image matches your original BMP file. You can also adjust the quality/size balance before converting when the target format supports compression.
Will transparent areas survive the conversion to PFM?
Transparency is kept whenever PFM actually supports an alpha channel. If the target format has none (like JPG), transparent areas are flattened onto a white background — that is a property of the format, not of this tool.
Can I convert several BMP files at once?
Yes — drop as many files as you like into the tool and they are converted in one batch. When more than one file comes out, everything is bundled into a ZIP for a single download.