Convert Image
Convert any browser-readable image to the format you actually need, with a quality control for the lossy formats. Useful when a platform only accepts one type, or when a design tool hands you an AVIF that your CMS will not display.
WebP is the best default for the web. If your browser cannot encode AVIF, Furtu produces a WebP instead and says so rather than handing you a mislabelled file.
Applies to JPG, WebP and AVIF. PNG is lossless, so this setting is ignored.
How convert image works
- Add your imagesDrop in any browser-readable image files. Furtu checks the file signature so a renamed file is caught before it reaches the decoder.
- Choose the target formatPick JPG, PNG, WebP or AVIF and set the quality. The quality setting only applies to the formats that have one.
- Download the converted filesEach image is re-encoded on your device and given the correct extension for the format that was actually written.
What you get
Move an image between JPG, PNG, WebP and AVIF in one step. Everything happens inside this page: the file is read by your browser, transformed in memory and handed straight back to you as a download. There is no upload queue, no waiting for a server, and nothing left behind when you close the tab.
Supported formats
Furtu accepts .jpg, .jpeg, .png, .webp, .avif, .gif, .bmp, .svg, .ico, .heic, .heif files up to 100 MB each, and processes up to 20 files in one run.
- Every file is checked against its real file signature, not just its name, so a renamed or corrupt file is rejected with an explanation instead of failing halfway through.
- Files over the limit are refused up front rather than after a long wait.
Limitations, stated up front
- Converting from a lossy format to another lossy format cannot undo the first lossy pass. Converting JPG to WebP is a clear win; converting a heavily compressed JPG to AVIF is not.
- AVIF output depends on your browser supporting AVIF encoding. Where it is missing, Furtu writes a WebP and says so in the note.
- Transparency is flattened onto a white background when converting to JPG.
- SVG is rejected: it is a vector format, and rasterising it here would silently change the artwork. Animated GIFs are rejected for the same reason a canvas cannot keep the animation.
Frequently asked questions
Which format should I pick?
WebP for anything on the web: it is smaller than JPG at the same perceived quality and supported by every current browser. PNG when you need hard edges, text or transparency preserved exactly. JPG when you are feeding something old — a print workflow, an email client, a CMS that predates WebP. AVIF compresses best of all, but only if your audience’s browsers support it.
Are the images uploaded to convert them?
No. Decoding and encoding both happen in your browser, so a design comp, a client photo or a screenshot of something confidential never travels to a third party.
What happens to transparency when I convert to JPG?
JPG has no transparency channel, so transparent pixels are filled with white. Convert to PNG or WebP if the transparent background is the point.
Why did I get a WebP when I asked for AVIF?
AVIF encoding is not available in every browser, and some quietly return a PNG instead. Furtu checks the bytes of the file it produced rather than trusting the browser, and if the result is not real AVIF it falls back to WebP, names the file correctly and tells you in the result note.