JPG, PNG, WebP or AVIF: which to use
Four formats cover almost everything. Here's when to use each one.
Updated October 2, 2026
| Format | Best for | Transparency | Opens everywhere? |
|---|---|---|---|
| JPG | Photos | No | Yes |
| PNG | Screenshots, logos, graphics with sharp edges | Yes | Yes |
| WebP | Photos and graphics for the web, smaller than JPG | Yes | Almost: all modern browsers and most apps |
| AVIF | Smallest files for photos | Yes | Modern browsers; some older apps can't open it |
JPG: the safe default for photos
JPG is lossy: it throws away detail you're unlikely to notice to make photos small. Every device and app opens it. It can't do transparency, and it handles sharp edges and text poorly, which show fuzzy halos.
PNG: for anything with sharp edges
PNG keeps every pixel exactly, so screenshots, logos and diagrams stay crisp, and it supports transparency. Photos as PNG are huge. Reducing a PNG to a smaller color palette, as Okaysize's Auto mode does for graphics, often cuts the size a lot with no visible change.
WebP and AVIF: smaller, for when you know they'll be supported
WebP produces noticeably smaller files than JPG at similar quality and supports transparency; it works in all modern browsers and most apps. AVIF is usually smaller still, but takes longer to create and isn't supported by some older apps and services. Use them for websites and anywhere you know they'll open.
The short answer
- Sending a photo to anyone: JPG.
- Screenshot, logo or anything with text: PNG.
- Images for your own website: WebP, or AVIF for the smallest files.
- Not sure: let Okaysize's Auto mode choose based on what's in the image.
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