Guide
PNG vs JPG vs WebP vs AVIF: which image format should you use?
Four formats, four different jobs. Here's how to pick the right one without guessing.
If you've ever right-clicked "Save image as" and hesitated over the format, you're not alone. JPG, PNG, WebP and AVIF all store pictures, but they make very different trade-offs between file size, image quality and features like transparency. Pick the wrong one and you either bloat your page or wreck your image. This guide explains what each format is actually good at, in plain terms, so you can choose with confidence.
The one-line summary
- JPG (JPEG) — best for photographs. Small files, no transparency, slight quality loss.
- PNG — best for logos, icons, screenshots and anything needing transparency or crisp edges.
- WebP — a modern all-rounder that beats both JPG and PNG on size, supported everywhere that matters today.
- AVIF — the newest and smallest, with the best quality-per-byte, but slower to encode and not supported by every old device.
How they actually differ
Two things separate these formats: whether they compress with loss or without loss, and whether they support transparency.
Lossy vs lossless
Lossy compression (JPG, and optionally WebP/AVIF) throws away detail your eye is unlikely to notice, in exchange for much smaller files. Save the same JPG repeatedly and that loss accumulates — edges get muddy and blocky. Lossless compression (PNG, and optionally WebP) keeps every pixel exactly, which is why PNG screenshots stay razor sharp but weigh a lot more than the equivalent JPG photo.
Transparency
PNG, WebP and AVIF can store a transparent background (an alpha channel), so a logo can sit on any colour. JPG cannot — it always fills the background, usually with white. That single fact decides a huge number of format choices: if you need transparency, JPG is out.
Side by side
| Format | Compression | Transparency | Typical use | Support |
|---|---|---|---|---|
| JPG | Lossy | No | Photos, complex images | Universal |
| PNG | Lossless | Yes | Logos, icons, screenshots, line art | Universal |
| WebP | Lossy or lossless | Yes | Almost anything on the web | All modern browsers |
| AVIF | Lossy or lossless | Yes | Web images where size matters most | Most modern browsers |
So which should I use?
For photographs
Reach for JPG if you need something that opens anywhere — email, an old CMS, a photo kiosk. For a website, WebP or AVIF will give you the same visual quality at a noticeably smaller size, which means faster pages. A good rule: keep a JPG master, serve WebP/AVIF to the web.
For logos, icons and screenshots
Use PNG. These images have sharp edges and flat colour, exactly what lossless compression handles well, and they often need transparency. A logo saved as JPG will show ugly halos around the edges and can't sit on a coloured background.
For a fast website
Modern sites lean on WebP as the safe default (broad support, big savings) and AVIF where you want the absolute smallest files and can accept slightly slower encoding. Both support transparency, so they can replace both JPG and PNG in many cases.
Converting between them
You rarely need to commit to one format forever. You can move an image between formats without re-shooting or re-designing it. To turn a PNG or JPG into a modern format, use the WebP converter. Coming from a modern format that a colleague can't open? The AVIF to JPG and PNG ⇆ JPG converters go the other way. All of them run entirely in your browser, so your images are never uploaded.
Once you've picked a format, the last step is usually to shrink the file for the web without visibly hurting it — that's what the image compressor is for, and it's the subject of its own guide below.