NOPPAWWebP images are often smaller because the format was designed with modern web delivery in mind. It can store image data more efficiently than older defaults in many common scenarios, but the explanation is not just one magical algorithm.
Different images respond differently to compression
A detailed photo, a flat-color screenshot, and a transparent graphic do not compress the same way. WebP often handles these cases more efficiently than older combinations, but the exact savings still depend on the content itself.
Format choice is only part of the equation
Even a strong format can produce a large result if the dimensions are oversized or the quality setting is too generous. That is why WebP often works best alongside sensible resizing and realistic compression targets.
Why comparisons still matter
Because image content varies, a WebP export can still be larger than the original in some cases. A browser-first tool should tell you when that happens. Routes such as JPG to WebP Converter and PNG to WebP Converter are most useful when they show the actual output difference instead of assuming success.
When a larger WebP is not necessarily wrong
If the converted file preserves more visible detail at the display size you care about, a slightly larger file might still be the better choice. Format decisions should stay tied to the real publishing goal, not just a single metric.
The practical takeaway
WebP is often smaller because it is good at web-oriented compression, but it is still one tool in a larger workflow. Right-size the image, choose the right format, and compare the result in context.