JPG vs PNG vs WebP: Which Image Format Should You Use?

Debates about image formats get technical fast. In practice, almost every decision comes down to three questions: Is it a photograph or a graphic? Does it need transparency? Does the destination accept modern formats?

The 30-second decision table

When JPG wins

JPG has been the default since 1992 and remains the safest choice when compatibility is uncertain — e-mail attachments, print shops, older CMS upload fields and government portals. Its weakness is that it is lossy and has no transparency, so it degrades every time you re-save, and it is a poor fit for sharp text.

When PNG wins

PNG is lossless: the image you save is the image you get back, forever. That makes it the right container for screenshots, diagrams, charts and anything containing text. The price is size — a photo saved as PNG can be 5–10× larger than the same photo as JPG, which is why “why is my site slow” so often traces back to a 6 MB PNG of a beach.

When WebP wins

WebP was designed to replace both: it supports lossy and lossless modes, transparency and animation, and is supported by Chrome, Edge, Firefox, Safari and Opera. For website images it is the default answer — 25–35% smaller than JPG at equal visual quality means faster pages and better Core Web Vitals with no design compromise. Convert in Image Converter and keep your originals.

Three costly mistakes

1. Saving screenshots as JPG. Text turns fuzzy and the file is not even smaller. Keep screenshots as PNG.
2. Saving photos as PNG for the web. You are shipping 5–10× the bytes for no visible benefit.
3. Re-saving a JPG repeatedly. Each save re-encodes and adds artefacts. Edit a PNG or RAW master, then export once.

And one habit that pays off: always convert a copy, never the only version you have. Formats change; originals are the thing you can always re-derive from.