What is near-lossless WebP?

A preprocessing step that adjusts pixel values so the lossy encoder can represent them far more cheaply, while keeping the result visually identical. It usually produces files much smaller than true lossless mode at effectively the same apparent quality.

Compress WebP images

Recompresses WebP as WebP. Useful when files were exported at a needlessly high quality, or with a fast encoder setting that left size on the table. The near-lossless mode is worth knowing about: it preprocesses the image so that lossy encoding becomes visually exact, which usually beats true lossless by a wide margin on size.

What to know

Near-lossless is available here and is not exposed by Pillow, the library behind most Python conversion scripts.
Re-encoding lossy WebP compounds loss. Use a high quality setting, or near-lossless.
Transparency and metadata are preserved.

Frequently asked questions

What is near-lossless WebP?: A preprocessing step that adjusts pixel values so the lossy encoder can represent them far more cheaply, while keeping the result visually identical. It usually produces files much smaller than true lossless mode at effectively the same apparent quality.