Private, local image processing
The selected file stays in this browser tab. LibraryCSS decodes it with the browser's image APIs, renders the result on a canvas, and creates the download locally. There is no upload endpoint and no account requirement.
How to get a clean result
Start with the original dimensions, make one type of adjustment at a time, and use PNG when transparency must survive. JPEG is usually smaller for photographs, while WebP balances size and detail for modern websites.
Browser limits
Very large images consume memory in proportion to their pixel count. If a phone photo feels slow, resize it before applying filters or censorship. Export support also depends on the browser's canvas encoder.