Add your X3F file
Drop one or more .x3f 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.
X3F to WEBP
Developing a .x3f camera file into .webp turns unprocessed sensor data into a finished image any app can open. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop X3F files here
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.About converting Sigma RAW to WebP image
Developing a .x3f camera file into .webp turns unprocessed sensor data into a finished image any app can open. An .x3f file is a Sigma RAW photograph captured with a Foveon X3 sensor, which stacks three photodiode layers so every pixel location records red, green, and blue directly. That architecture makes .x3f fundamentally different from Bayer-pattern RAW files — there is no color mosaic to demosaic — and gives Foveon images their reputation for peculiar, film-like per-pixel sharpness.
A .webp file is Google's web-oriented image format, offering both lossy and lossless compression plus alpha and animation in one container. At equivalent visual quality, .webp files typically undercut JPEG by 25-35 percent, which is why CDNs and site optimizers convert to it aggressively. For this route the practical draw is smaller than JPEG for photos and usually smaller than PNG for graphics and one format covers lossy, lossless, alpha, and animation — balanced against mandatory 4:2:0 subsampling in lossy mode caps color fidelity below high-quality JPEG or AVIF, which is worth knowing before you commit a large batch.
Why convert X3F to WEBP?
The practical trigger for this conversion is usually a mismatch: with .x3f, third-party support is the weakest of any major RAW format; Sigma Photo Pro is often the only full-fidelity path. Switching to .webp buys you smaller than JPEG for photos and usually smaller than PNG for graphics, which is why it is the better fit for serving photos and graphics on websites where bandwidth and Core Web Vitals matter. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
X3F vs WEBP at a glance
| Aspect | Sigma RAW (.x3f) | WebP image (.webp) |
|---|---|---|
| Format type | Lossless — every pixel or sample is preserved exactly | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | records three stacked layers per photosite, exploiting silicon's wavelength-dependent light absorption instead of a color filter array | lossy mode encodes VP8 intra frames with block prediction; lossless mode uses its own dedicated coding with spatial predictors and color transforms |
| Strongest at | base-ISO landscape, product, and architecture work where Foveon detail shines | serving photos and graphics on websites where bandwidth and Core Web Vitals matter |
| Weak spot | third-party support is the weakest of any major RAW format; Sigma Photo Pro is often the only full-fidelity path | mandatory 4:2:0 subsampling in lossy mode caps color fidelity below high-quality JPEG or AVIF |
| Metadata | eXIF fields and Sigma's property lists are embedded in the container, but MakerNote conventions differ enough from Bayer vendors that generic tools extract less; ExifTool provides the most complete parsing | eXIF and XMP travel in dedicated RIFF chunks and ICC profiles are supported, though a fair amount of conversion software strips metadata by default when writing WebP |
Pick WEBP as the output
Select .webp in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if WEBP is selectable, the route is real and validated.
Convert on your device
Press Convert. A LibRaw WebAssembly decoder demosaics the sensor data in your browser and renders a developed image ready for export.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid WEBP file. Outputs keep the original filename with the .webp extension.
X3F to WEBP questions, answered
Will converting X3F to WEBP lose quality?
Some. Since x3f is lossless-oriented and webp is lossy-oriented, the encoder will discard detail it judges least visible; the quality slider controls how aggressive that is. Keep the original .x3f if you may need a pristine master later.
Is it private to convert X3F files here?
Yes — the .x3f file is processed inside your browser tab and never uploaded. A LibRaw WebAssembly decoder demosaics the sensor data in your browser and renders a developed image ready for export. Close the tab and the file is gone from memory.
Where will the WEBP file work?
Chrome, Edge, Firefox, and Safari (since version 14 in 2020) all decode WebP natively, as do Android and current versions of Windows and macOS system viewers. Older tools from before roughly 2020 — legacy Photoshop releases, older email clients, many kiosk printers — commonly fail on it, so JPEG or PNG remains the safer handoff format outside the browser.
Will the WEBP file be bigger or smaller than my X3F?
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.
What happens to the metadata in my X3F file?
In .x3f, eXIF fields and Sigma's property lists are embedded in the container, but MakerNote conventions differ enough from Bayer vendors that generic tools extract less; ExifTool provides the most complete parsing. 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.