JPG vs PNG vs WebP vs AVIF: Which Image Format Should You Use?
Every image format is a different trade-off between file size, quality, compatibility and features like transparency. Pick well and your files are small and open everywhere; pick badly and you get 30 MB scans or logos with jagged white edges. Here is what each format is actually for.
Privacy-first: every image is processed locally in your browser. Nothing is uploaded, stored or transmitted to any server.
JPG — the universal photo format
JPG (1992) compresses photographs by discarding detail the eye barely notices, tunable via a quality setting. At quality 75–85 files are small and look excellent; every device and program on earth opens them. Its limits: no transparency, and each re-save loses a little more detail. Use it for photos that need to work absolutely anywhere.
PNG — lossless, with transparency
PNG stores pixels exactly and supports full alpha transparency, which makes it the standard for logos, screenshots, UI graphics and any image that will be edited repeatedly. The cost is size: photographs stored as PNG balloon to many times their JPG size, because photographic noise does not compress losslessly. Use PNG for graphics and working copies, not for delivering photos.
WebP — the modern web default
WebP does both jobs: lossy compression around 25–35% smaller than equivalent-quality JPG, and lossless-with-transparency far smaller than PNG. Every browser has supported it since 2020. Its only weakness is outside the web — older desktop software, printers and some upload forms still reject it. Use WebP for anything displayed on a website.
AVIF — smallest files, newest format
AVIF, built on the AV1 video codec, produces the smallest files of any mainstream format — often half the size of JPG at the same quality — and supports transparency and HDR. Browser support is now universal, but tooling and non-web software lag behind. Use it where bytes matter most and you control the delivery, with a fallback for older environments.
GIF, SVG and HEIC — the specialists
GIF survives purely for simple animations; for still images it is obsolete (256 colors, huge files). SVG is not pixels at all but vector geometry — perfect for icons and logos that must scale, meaningless for photos. HEIC is Apple’s efficient camera format: great on-device, awkward everywhere else, and usually converted to JPG the moment a file leaves the Apple ecosystem.
The decision, condensed
Photo for general sharing → JPG. Anything on a website → WebP (or AVIF if you can manage fallbacks). Logo, screenshot or transparency → PNG (WebP if web-only). Needs to scale to any size → SVG. From an iPhone and headed elsewhere → convert HEIC to JPG. When in doubt, JPG for photos and PNG for graphics is never a disaster.