How to use it

Drop one or more images on the box above, paste with Ctrl+V (Cmd+V on a Mac), or click to choose files.
Pick the format to save: JPG, PNG or WebP.
Adjust the quality if needed (JPG and WebP), and pick a maximum long side for lighter files.
Click Save on each image, or Save all. The new file keeps the name: photo.webp becomes photo.jpg.

What it does

Reads any image your browser can open: JPG, PNG, WebP, GIF, BMP, SVG, and AVIF in modern browsers.
JPG gets a white background for transparent areas instead of black. PNG and WebP keep transparency.
SVG images are rendered sharp, at least 1,024 px on the long side.
If an image is already in the format you picked and needs no resizing, the original file is kept as is.
Shows the size before and after, so you see how much lighter it is.

It never uploads images. Every step happens in the browser. Close the tab and they are gone from memory.
It cannot open every format. HEIC (iPhone photos) opens only in Safari; TIFF depends on the browser. On a Mac, 1xQuickConvertFormat converts HEIC to JPG, PNG, WebP, AVIF, GIF, TIFF, BMP and ICO.
No animation. Animated images are saved as a still of their first frame.
No metadata. The new image does not carry the original's camera data (EXIF).

The image is on a web page: the Save Image as JPG, PNG, WebP extension lets you right-click and save it in the right format.
Hundreds of images, or video, PDF and Office files too: 1xQuickConvertFormat on a Mac.

No. There is no server receiving images. They are decoded and saved by your browser's own image engine.

Some browsers, Safari for example, cannot write WebP. The option is then disabled and you can save PNG or JPG.

It is the JPG and WebP compression level, from 50 to 100. At 92 the image looks virtually unchanged and is much lighter than at 100.

Browsers on Windows usually cannot open HEIC. Open this page in Safari on an iPhone or Mac, or use 1xQuickConvertFormat on a Mac.