JPGをWebPに変換 — 無料

The WebP quality slider (20-100) trades file size for detail — 75-85 is the sweet spot for most photos, giving the 25-35% size saving over JPG that WebP is known for without visible artifacts. Drop it toward 60 for background or thumbnail images where file size matters more than pixel-perfect sharpness.

Turning on Lossless mode disables the quality slider and encodes every pixel exactly as in the source JPG, producing a larger file than a compressed conversion. Use it for screenshots, graphics, logos or any image where you plan further edits and can't afford compression artifacts — for ordinary photos, the quality slider gives a much smaller file at visually identical results.

Yes — switch to Batch mode, drop in multiple JPG files, and the tool converts each one with your chosen quality/lossless settings and packages them into a single downloadable ZIP. Batch conversion is a Premium feature; single-file conversion stays free and unlimited.

For ordinary product photography, leave Lossless off and set quality to 80-90 — you get a dramatically smaller file than the original JPG with no visible quality loss on a web page. Reserve Lossless mode for flat-color graphics like logos or screenshots layered into product photos, where compression artifacts around sharp edges and text would actually be noticeable.