Images
WebP, AVIF, PNG or JPG: Choosing the Right Image Format
Every image you save or upload lands in a format, and that choice quietly decides how sharp the picture looks, how big the file is, and whether the edges stay crisp. Pick the wrong one and you either bloat your page with needless megabytes or smear a clean logo into a blurry mess. This guide walks through the five formats you will actually meet — JPG, PNG, WebP, AVIF and GIF — and when each is the right tool.
Lossy vs lossless, in one minute
Before the formats, one idea explains almost everything that follows. Lossy compression throws away some image data to make the file smaller — usually detail your eye barely notices. Save a lossy file again and again and the quality slowly degrades. Lossless compression shrinks the file without discarding anything, so the image reopens exactly as it went in, but the files are larger. Lossy wins for photos; lossless wins for sharp graphics and text.
The five formats
JPG (JPEG) is lossy and the old workhorse of photography. It handles the millions of subtle colour gradients in a photo beautifully and keeps files small. Its weaknesses are real, though: it has no transparency, and at high compression it produces visible blocky "artefacts" and halos, especially around hard edges and text.
PNG is lossless and supports transparency. That makes it ideal for logos, screenshots, icons, and any graphic with sharp edges or text, where JPG's artefacts would show. The trade-off is size: for a full photograph a PNG is usually much larger than the equivalent JPG.
WebP is the modern all-rounder. It can be either lossy or lossless, supports transparency, and even does animation. At similar quality it is typically around 25–35% smaller than JPG or PNG, and it is now supported in every modern browser. For most websites it is the sensible default.
AVIF is the newest of the group and generally has the best compression here — often smaller than WebP at the same quality. It supports transparency and HDR colour. The catches: encoding is noticeably slower, and while browser support is good, it still trails WebP by a little, so a fallback is wise.
GIF is legacy. It is limited to just 256 colours, which makes it poor for photos, and today it survives mainly for simple animations. For almost any job a GIF once did, an animated WebP or AVIF — or a short video — will look better and weigh far less.
Quick comparison
| Format | Type | Transparency | Animation | Best for |
|---|---|---|---|---|
| JPG | Lossy | No | No | Photographs |
| PNG | Lossless | Yes | No | Logos, screenshots, sharp graphics |
| WebP | Lossy or lossless | Yes | Yes | General web use |
| AVIF | Lossy or lossless | Yes | Yes | Maximum compression |
| GIF | Lossless (256 colours) | Yes | Yes | Simple legacy animation |
So which should you use?
You can skip the agonising with a few rules of thumb:
- Photographs → reach for WebP or AVIF, with a JPG fallback for anything that must work everywhere.
- Graphics, logos, or anything needing transparency → use WebP, or PNG when you want maximum compatibility and lossless edges.
- Maximum savings → use AVIF, and keep a WebP or JPG fallback for older clients.
The good news is that none of this locks you in. These formats all describe the same picture, so you can convert between them freely — export a master PNG, then generate WebP and AVIF versions for the web, keeping a JPG on hand as a safety net.
The takeaway
There is no single "best" image format — only the right one for the job. Lean on WebP as your everyday default, reach for AVIF when every kilobyte counts, keep PNG for crisp graphics and transparency, and treat JPG as the universal fallback. Match the format to the content and you get smaller pages and sharper images at the same time.