JPG vs PNG vs WebP vs AVIF: which image format should you use?

Choosing an image format is a trade-off between file size, quality, transparency and compatibility. Here is how the four most common formats compare, and a simple way to choose.

JPG: the universal photo format

JPG (or JPEG) uses lossy compression: it discards detail the eye barely notices, so photos become much smaller. It has no transparency and can show blocky artefacts at low quality or around sharp text. It works everywhere, which is why online forms ask for it.

Use it for: photographs, email attachments and form uploads.

PNG: lossless with transparency

PNG keeps every pixel exactly and supports transparency. That makes it ideal for logos, icons and screenshots with sharp edges, but photos saved as PNG are very large. Reducing the number of colours (palette PNG) can shrink a PNG a lot with little visible change.

Use it for: logos, interface screenshots, graphics with text or transparency.

WebP: the modern all-rounder

WebP can be lossy or lossless and supports transparency. At comparable quality it is usually smaller than JPG and PNG, and all modern browsers support it. It is a strong default for websites.

Use it for: website images where you control the page.

AVIF: often the smallest

AVIF is newer and typically compresses better than WebP, especially for photos, and also supports transparency. Encoding can be slower and support, while wide in modern browsers, is not as universal as JPG or PNG.

Use it for: performance-focused sites with modern audiences, with a fallback when needed.

A simple decision guide

Uploading to a form or sending to someone? JPG.
Logo, icon or screenshot? PNG (or WebP).
Putting it on a website? WebP, or AVIF with a fallback.
Need transparency and small size? WebP or AVIF.

Convert in your browser

You do not need to upload anything. Try the JPG to WebP or PNG to JPG converters, or use the compressor below to see how much a quality change saves. See the full format guide for a side-by-side table.