HDR to PGM Converter
Processing entirely on your device — large files may take a moment.
Convert PGM grayscale to PNG/JPG for viewing, or emit PGM for scientific pipelines that require raw pixel honesty. If your files are still in HDR format, this page is the shortcut: HDR (Radiance RGBE) stores floating-point high-dynamic-range pixels — the format of lighting data and HDRI environment maps.
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 to convert HDR to PGM
- 1
Select your files
Drag & drop your HDR 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 PGM". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted PGM file individually, or grab everything at once as a ZIP archive.
About the HDR format
HDR (Radiance RGBE) is the veteran high-dynamic-range format of lighting research and 3D rendering: pixels stored as a shared 8-bit exponent plus per-channel mantissas, letting one file hold both a sun and a shadow with no clipping. HDRI environment maps for 3D scenes are almost always HDR files.
Standard image viewers show it badly or not at all, because the values can exceed what a screen can display. Converting HDR to PNG tone-maps the file into an 8-bit preview — good for quick inspection, though the floating-point original remains the render-grade master.
+ Strengths
- ✓True high-dynamic-range values
- ✓The standard of HDRI environment maps
- ✓Compact for its precision
! Limitations
- −Not display-ready — needs tone mapping
- −Viewer support is scarce
About the PGM format
PGM is netpbm's grayscale format: a two-line text header, then raw 8 or 16-bit luminance samples with no compression and no metadata. That raw honesty made it the default exchange format of computer-vision research, image-processing coursework and any pipeline where "what you read is exactly the pixel value" matters.
Converting PGM to PNG or JPG just normalizes it for humans; converting back down preserves every value bit-exactly when the pipeline needs numbers, not pictures.
+ Strengths
- ✓Bit-exact pixel values, no color management surprises
- ✓16-bit depth support
- ✓Trivially parseable
! Limitations
- −No compression — large files
- −Grayscale only
- −No embedded metadata
Why convert HDR to PGM?
There is a concrete reason this conversion exists: Not display-ready — needs tone mapping PGM sidesteps that — Bit-exact pixel values, no color management surprises If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this HDR to PGM 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 HDR to PGM?
No — PGM is a lossless format, so every pixel of the converted image matches your original HDR file. You can also adjust the quality/size balance before converting when the target format supports compression.
Can I convert several HDR 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.
What happens to EXIF data and other metadata?
Conversions here re-encode the image, and re-encoding generally does not carry the original metadata over. If the EXIF data of your HDR files matters (camera model, GPS, timestamps), keep the original file as the master and treat the converted copy as the shareable version.