Which format should you pick?
- JPG is the format every phone, camera, website and print service understands. It is lossy, so it throws away detail you are unlikely to notice to keep photos small. It cannot be transparent, and each time you re-save a JPG a little more quality is lost.
- PNG is lossless: it stores every pixel exactly and supports transparency. That makes it right for screenshots, logos, text and line art, and for working copies you will edit again. Photos saved as PNG are very large.
- WebP was made for the web. It can be lossy or lossless, supports transparency, and is usually smaller than a JPG or PNG with a similar look. Current versions of Chrome, Edge, Firefox and Safari open it, but some older programs and upload forms do not.
- AVIF often makes the smallest files of all and also supports transparency. It takes longer to create, especially for large photos, and it is less widely supported than WebP, so check where the file has to be opened.
Not sure? Use JPG when the file must open anywhere, PNG when you need exact pixels or transparency, and WebP when the file is for a website.
What changes when you convert
- Quality. Going to JPG, lossy WebP or AVIF discards some detail, and doing it more than once adds up. Going to PNG or lossless WebP loses nothing further, but it cannot bring back detail that an earlier lossy format already removed.
- Transparency. PNG, WebP and AVIF keep it. JPG cannot, so see-through areas are filled with a colour you choose, white by default. Pixels that are almost fully transparent can change slightly in colour, because browsers store see-through pictures in a form that rounds them.
- Metadata. Camera details, the date and the GPS location are removed by default, which is useful before you share a photo. Choose Keep to copy the EXIF block from JPG, PNG and WebP originals into JPG, PNG and WebP results. AVIF results cannot hold it here.
- Rotation and colour. Photos that your camera stored sideways with an orientation tag are turned the right way up. Colours are converted to sRGB, so a wide-gamut photo (such as Display P3) can look slightly less vivid. The colour profile is not embedded.
The list shows the size of each result and how much smaller or larger it is than the original, so you can see right away whether a conversion was worth it.
HEIC, TIFF, SVG, GIF and ICO files
- HEIC is the format iPhones use by default. Safari can usually open it on its own. In other browsers a HEIC converter downloads from this site the first time you add such a file (a few megabytes) and then runs on your device.
- TIFF files open too. If a TIFF has several pages, the largest one is used.
- SVG has no fixed size in pixels, so you choose how wide to draw it and the height follows its shape. Scripts inside an SVG do not run and nothing it links to is fetched.
- GIF files give their first frame, and animated WebP files do too. ICO files give the largest picture inside them.
Big images and big batches
A decoded image takes four bytes per pixel, and a conversion keeps several copies at once, so a 48 megapixel photo (8000 by 6000) can need several hundred megabytes of memory while it is converted. To keep your tab alive, images above 100 megapixels are refused with a clear message, and large images in a batch are converted one at a time while small ones run side by side.
Several images are converted in parallel using your processor cores. You can cancel at any time: files that are already done keep their results. Converting to PNG with optimisation on takes the longest, followed by AVIF. For very large images the PNG optimiser is skipped automatically to keep things moving.
If a conversion fails because the browser runs out of memory, try fewer images at once, close other tabs, or use a desktop computer, which copes with big photos much better than a phone. For specific jobs, see JPG to PNG, PNG to JPG, JPG to WebP, WebP to JPG, PNG to WebP and WebP to PNG.