JPEG for photography
JPEG is a common choice for photographs where transparency is unnecessary. Its lossy compression can reduce file size significantly.
PNG for precise graphics
PNG preserves exact pixel data and supports transparency, but photo files can become large.
WebP for modern delivery
WebP supports lossy and lossless compression as well as transparency, often at smaller file sizes than older formats.
Test actual files
Format performance depends on the image. Compare representative images rather than assuming one format always wins.
Further reading
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