Convert an image
Format conversion is usually about compatibility: something will not accept the file you have. Occasionally it is about size, because some formats simply store the same picture more efficiently than others.
Every converter below runs on your own device.
Converters
Between image formats, and between images and documents.
Specific conversions
Pages that cover one conversion and its quirks in full.
Which format should you actually use?
| Format | Use it for | Avoid it for |
|---|---|---|
| JPEG | Photographs, anything with continuous tone, anywhere compatibility matters most | Line art, screenshots, anything needing transparency |
| PNG | Logos, screenshots, line art, anything with transparency | Photographs — the files are enormous for no visible benefit |
| WebP | Web delivery of anything; 25–35% smaller than JPEG at matching quality, and it supports transparency | Upload forms, which still frequently reject it |
| HEIC | Nothing, deliberately — it is a capture format, not a sharing one | Sending to anyone, or uploading anywhere outside Apple's ecosystem |
Converting does not undo compression
This catches people out constantly. Converting a heavily-compressed JPEG to PNG does not restore the lost detail — it stores the damaged version losslessly, usually in a much larger file. You get the worst of both.
The same applies in reverse: if you have a PNG you need smaller, converting to JPEG genuinely helps, but converting back later will not recover anything. Always keep the original of anything you may need again.
Transparency survives only some conversions
PNG and WebP support transparency; JPEG does not. Convert a transparent PNG to JPEG and every transparent pixel becomes solid white — which is fine for a photo on a white page and ruinous for a logo meant to sit on a coloured background. WebP is the way to keep transparency and still get a small file.
If it is a logo you are working with, see the logo background guide.