6 minute guide
WebP vs AVIF vs JPEG: choose by the image
There is no permanently smallest format for every image. Start with the content, browser requirements and transparency needs, then compare outputs from the same source.
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Practical image optimization guides
Practical, evidence-led guides to image formats, target file sizes and finding oversized webpage images.
Three focused guides · reviewed September 14, 2026Published guides
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7 minute guide
How target-size image compression works
A target such as 200 KB is a constraint, not a quality setting. A useful compressor searches for the best tested output under that ceiling and admits when quality alone cannot get there.
8 minute guide
How to find large images on a website
A useful audit separates transfer weight, intrinsic pixel dimensions and rendered size. One number cannot tell you whether an image is actually a problem.