Start with dimensions
A 4000px photo on a 400px card wastes bandwidth. Resize to the display size first, then compress. That two-step path usually beats compression alone.
Pick a format
- JPEG for photos.
- PNG when you need transparency.
- WebP when your audience’s browsers support it for smaller files.
Use Compress Image on korisa.app
Upload in the browser, tune quality, and download an optimized file — without sending the image to a random server.