Convert image format
Switch any image between JPG, PNG, WebP and AVIF. Convert a whole batch at once and download a ZIP.
Files never leave your deviceHow to convert an image
- Drop one or more JPG, PNG, WebP or AVIF files onto the box above, or paste an image from your clipboard.
- Choose the format you want in Convert to. For lossy formats a Quality slider appears.
- Press the convert button. Each file shows its new size when it is done.
- Download files individually, or press Download all as ZIP to get the whole batch.
Converted files keep their original name with the new extension. If the source already has that extension, -converted is added so you never overwrite anything.
Private by design
The conversion runs in your browser with WebAssembly codecs, not on a server. Your pictures are decoded, converted and encoded in a background thread, so the page stays smooth while a batch is processed, and the files never leave your device. The same code runs offline after your first visit.
Which format should you pick?
JPG is the universal choice for photographs. Every app, website and printer understands it. It cannot store transparency.
PNG is lossless and supports transparency, which makes it the right choice for logos, screenshots and graphics with sharp edges. Photographs saved as PNG are much larger than the same picture as JPG.
WebP was designed for the web. It handles photos and transparency, and files are typically a quarter to a third smaller than JPG. Every current browser, and most apps from the last few years, can open it.
AVIF compresses best of all, often half the size of a JPG at similar quality, and supports transparency and high dynamic range. Encoding is slower, and a few older programs cannot open it yet.
Notes on quality
- Converting from one lossy format to another (for example JPG to WebP) adds a second round of compression. Use a high quality setting, or start from the original or a PNG if you have one.
- Converting a lossy image to PNG does not restore lost detail; it just stores the current pixels without further loss.
- When a transparent PNG is converted to JPG, transparent areas turn white.
- Metadata such as GPS location and camera model is not copied into the converted file. Rotation is applied to the pixels first, so pictures are not turned sideways.
- For iPhone HEIC photos use the dedicated HEIC converter, and to change the dimensions of a picture use the resize tool.
Frequently asked questions
Which format is best for the web?
WebP and AVIF are usually 25 to 50 percent smaller than JPG at the same quality. AVIF compresses best but encodes slower. JPG remains the most compatible.
What happens to transparency?
PNG, WebP and AVIF keep transparency. JPG cannot, so transparent areas are filled with white when you convert to JPG.
Is AVIF supported everywhere?
All current major browsers can display AVIF. Some older apps and email clients cannot, in which case choose WebP or JPG.
Are my files uploaded anywhere? How can I check?
No. The image converter runs entirely in your browser using JavaScript and WebAssembly, so your files never leave your device. You can verify it: open your browser's DevTools (F12, or Cmd+Option+I on a Mac), switch to the Network tab, tick "Preserve log", clear the list and process a file. You will only see requests for this site's own static files, never one that carries your data. You can also turn on "Offline" in the Network tab (or disconnect from the internet) once the page has loaded, and the tool keeps working.
Does it work offline?
Yes. After your first visit a service worker saves the tool to your device, so it opens and works without a connection. Only advertising needs the internet; the processing never does.