Choosing the wrong image format can make a website slow, a logo blurry or an upload form reject your file. The good news: for almost every situation, the right choice comes down to a few simple rules. This guide explains how the four most common formats differ and when to use each.
Quick comparison
| JPG | PNG | WebP | AVIF | |
|---|---|---|---|---|
| Compression | Lossy | Lossless | Both | Both |
| Transparency | No | Yes | Yes | Yes |
| Animation | No | APNG only | Yes | Yes |
| Size vs JPG (photos) | 100% | 200–500% | ~70% | ~50% |
| Compatibility | Everywhere | Everywhere | All modern browsers | Modern browsers |
JPG (JPEG) — the universal photo format
JPG has existed since 1992 and is supported by every device, program and website. It uses lossy compression: it throws away detail that the eye barely notices, which makes photos small. The trade-off is that sharp edges, text and flat colours can get blurry “artifacts”, and JPG cannot store transparency.
Use JPG for: photos, upload forms with size limits, email attachments, anything that must open everywhere.
PNG — lossless and transparent
PNG keeps every pixel exactly. That makes it perfect for screenshots, logos, icons, diagrams and text, and it supports full transparency. The downside is size: a photo saved as PNG is often 3–5 times larger than the same photo as JPG.
Use PNG for: logos, graphics with text, screenshots, images with transparent backgrounds, files you will keep editing.
WebP — the modern all-rounder
Created by Google in 2010, WebP supports both lossy and lossless compression, transparency and animation. Lossy WebP is typically 25–35% smaller than JPG at the same visual quality. All current browsers support it, but some desktop software and upload forms still do not.
Use WebP for: images on your own website. Keep a JPG or PNG copy for sharing.
AVIF — the smallest files
AVIF is based on the AV1 video codec and offers the best compression of the four — often half the size of JPG. It also supports HDR and wide colour. Encoding is slower and support in older software is limited.
Use AVIF for: high-traffic websites where every kilobyte counts, with a JPG or WebP fallback.
What about HEIC?
HEIC is Apple’s camera format. It is efficient but poorly supported outside Apple devices. Convert it to JPG before sharing — see What is HEIC.
Simple rules
- Photo that must work everywhere → JPG.
- Logo, screenshot or transparent background → PNG.
- Images on your own website → WebP (or AVIF with a fallback).
- File refused by a program → convert it with our WebP to PNG, AVIF to JPG or HEIC to JPG tools.