Four formats cover nearly every image you will save or share: JPG, PNG, WebP and AVIF. They differ in how they compress, whether they keep transparency, and which apps will open them. Here is how to choose.
JPG: the universal photo format
JPEG (saved as .jpg or .jpeg) has been the standard for photographs since the 1990s. It uses lossy compression tuned to how eyes see: it discards fine colour detail you are unlikely to notice. At quality 80–85 a photo is typically a tenth of its uncompressed size and looks the same.
Its weaknesses are sharp edges and flat colour. Text, logos and screenshots get fuzzy halos (“artefacts”). JPG has no transparency, and every re-save loses a little more detail. But every device, app, website and upload form accepts it.
PNG: lossless, sharp and transparent
PNG compresses without losing anything, so screenshots, diagrams, logos and text stay perfectly crisp, and it supports full transparency. The price is size: a photo saved as PNG is often 5–10 times larger than a good JPG.
Use PNG for screenshots, UI images, graphics with text, and anything you will edit again. Avoid it for photos you are sending or uploading.
WebP: smaller files for the web
WebP, from Google, does both lossy and lossless compression, supports transparency and animation, and typically produces files 25–35% smaller than JPG or PNG at similar quality. Every current browser supports it, which is why many websites now serve WebP.
The catch is outside the browser. Some older desktop software, printing services and government forms still refuse WebP, which is why people so often need to convert WebP to JPG.
AVIF: the most efficient, still catching up
AVIF is based on the AV1 video codec. It compresses better than WebP, often half the size of a comparable JPG, and handles HDR and wide colour. Current Chrome, Edge, Firefox and Safari display it.
Encoding AVIF is slow, and support in photo editors, messaging apps and operating-system previews is patchier than WebP. It is excellent for websites that can offer a fallback, less so for files you send to other people.
Side by side
| JPG | PNG | WebP | AVIF | |
|---|---|---|---|---|
| Compression | Lossy | Lossless | Both | Both |
| Transparency | No | Yes | Yes | Yes |
| Animation | No | APNG only | Yes | Yes |
| Photo size (relative) | 100% | 500%+ | ~70% | ~50% |
| Opens everywhere | Yes | Yes | Browsers, most apps | Browsers, some apps |
Sizes are typical for photographs at similar visual quality; real results vary with the image.
What to use when
- Sending or uploading a photo: JPG. It will be accepted everywhere.
- Screenshots and graphics with text: PNG.
- Images on your own website: WebP, or AVIF with a WebP/JPG fallback.
- A logo with a transparent background: PNG for sharing, SVG if you have a vector original, WebP on the web.
- iPhone photos (HEIC) that won’t open: convert to JPG. See why HEIC won’t open on Windows.
Sources: Google, WebP overview; Alliance for Open Media, AVIF specification; W3C PNG specification.