How it works
Pick a format and a setting
Open an image and choose the output: JPEG (MozJPEG), WebP, PNG (OxiPNG) or AVIF. The result updates as you move the slider, and the panel shows the original size, the compressed size and the percentage change.
For JPEG, WebP and AVIF the slider is Quality from 1 to 100: lower is smaller and softer. PNG is lossless, so its slider is Effort from 1 to 6, which only tries harder to pack the same pixels.
Compare before you save
Drag the comparison handle across the picture to see original and compressed side by side at full size. JPEG has no transparency, so transparent areas turn white when you pick it.
