WEBP vs JPEG vs PNG: Which Image Format Should You Use?

Choosing the right image format is one of the fastest ways to shrink a website. The three formats every web publisher should know — JPEG, PNG and WEBP — were designed for different jobs, and picking the wrong one can leave your pages either bloated or blurry. This guide compares how each format compresses data, where it shines, and when to avoid it.

JPEG — the universal workhorse

JPEG was created in 1992 specifically for photographs. It uses lossy compression, which means it permanently discards visual information that the human eye is poor at perceiving, such as tiny colour variations inside smooth gradients. The result is a file that can be ten to twenty times smaller than the uncompressed original with no obvious artefacts at quality settings of 75 or higher. JPEG does not support transparency and is a poor choice for logos or text, where compression artefacts turn crisp edges into blurry halos. Its strength is universal support: every browser, image editor and camera in the world can read and write JPEG, which makes it the safest default for photographs shared online.

PNG — lossless and transparent

PNG uses lossless compression, so the decoded image is pixel-for-pixel identical to the original. It also supports an alpha channel, which means parts of the image can be fully or partially transparent. That combination makes PNG the right choice for logos, icons, UI screenshots, diagrams and any graphic with sharp edges or readable text. The trade-off is file size: a photographic PNG is often several times larger than the same image saved as a JPEG, because lossless encoding cannot discard the fine, noisy detail that fills a photograph. For the web, PNG is best reserved for graphics rather than photos.

WEBP — modern, smaller, flexible

WEBP is Google's modern format, introduced in 2010. It supports both lossy and lossless compression, includes an alpha channel for transparency, and can even animate. In practice a lossy WEBP file is typically 25 to 35 percent smaller than an equivalent JPEG at the same visual quality, while a lossless WEBP is around 20 percent smaller than the PNG of the same image. Today every major browser supports WEBP, so it is an excellent default for new projects. The one remaining caveat is very old software and some content-management pipelines that still expect JPEG or PNG, which is why PhotoShrinker exports optimised JPEG by default and lets advanced users switch to WEBP or PNG when their stack supports it.

Quick decision guide

Use JPEG for photographs destined for the open web where compatibility matters most. Use PNG for graphics, logos and screenshots that need pixel-perfect edges or transparency. Use WEBP when you control the publishing pipeline and want the smallest files modern browsers can display. Whichever format you choose, the single most effective optimisation is compressing the image to the lowest quality your eyes still accept — and that is exactly what PhotoShrinker does in your browser, privately and instantly.