JPG vs PNG vs WebP — Which Should You Use?
Updated 8 September 2026
Most format confusion comes from treating this as a quality question when it is really a content question. The right format depends on what is in the image — photographs and flat-colour graphics compress by completely different mechanisms, and picking the wrong one can multiply your file size for no visible benefit.
JPG for photographs
JPEG compression works by discarding detail the eye is unlikely to notice, which suits continuous-tone imagery where colours shift gradually — skies, skin, foliage, anything photographic. It has no transparency support and it is lossy, meaning every save discards a little more, so repeatedly opening and re-saving a JPG degrades it over time. Use it for photographs headed somewhere with a size limit, and keep a master copy in a lossless format if you will keep editing.
PNG for graphics, screenshots and transparency
PNG is lossless and compresses by finding repeated patterns, which makes it excellent for large flat areas of identical colour — logos, icons, diagrams, UI screenshots. It is the only one of the three with universally supported transparency. The cost is size: a photograph saved as PNG is typically several times larger than the JPG equivalent with no visible difference, because photographs contain almost no repetition for PNG to exploit.
WebP when you control the destination
WebP compresses roughly 25 to 35 percent better than JPG at similar quality and supports transparency like PNG, which makes it strictly better than both on paper. The catch is compatibility: every current browser handles it, but some older desktop software, a few upload forms, and various government portals still reject it. Use WebP for images on a website you control. Avoid it for files you are sending to someone whose software you cannot predict.
The practical decision
Is it a photograph with no transparency, going somewhere you do not control? JPG. Does it need transparency, or is it a logo, diagram, or screenshot with sharp edges? PNG. Is it going on your own website and you care about load speed? WebP, with a JPG or PNG fallback if you support older clients. That covers almost every real case without needing to think about compression theory.
Converting does not recover quality
This trips people up constantly. Converting a JPG to PNG does not undo the compression artefacts already baked in — it preserves them losslessly in a much larger file. Quality lost in a lossy format is gone permanently. Conversion changes the container and the future behaviour of the file, never its existing content, so always convert from the highest-quality source you have rather than from a file that has already been through a round trip.
Frequently asked questions
- Will converting my JPG to PNG make it look better?
- No. PNG stores exactly what is already there, artefacts included. It prevents further loss but recovers nothing.
- Why is my PNG photo so large?
- PNG compresses by finding repeated colour patterns, which photographs do not have. For photos without transparency, JPG or WebP will be far smaller at the same visible quality.
- Should I switch my website to WebP?
- For most sites yes — the file size reduction is real and every current browser supports it. Keep fallbacks if a meaningful share of your audience uses older software.