How this tool works
The shape is cut by drawing it as a path on the canvas and keeping only what falls inside it. Three shapes are available: rounded corners with a radius you set, a circle inscribed in the image, and a squircle — the continuous curve used for app icons on iOS and increasingly elsewhere, which reads as rounder than a rounded rectangle without the visible point where a circular corner meets a straight edge.
What sits outside the shape is either transparent or a colour you choose. That decision drives the format: transparency needs PNG or WebP, and choosing JPEG flattens the image onto the colour first, since JPEG has no alpha channel. A circle on a non-square image is inscribed in the shorter dimension and centred.
Getting a clean edge
- Transparency means PNG or WebP: a rounded JPEG is a rectangle with coloured corners. It will look correct only against a background of exactly that colour, and wrong everywhere else.
- Match the radius to the size: a radius that looks right on a large image is barely visible on a thumbnail. Corners are usually judged as a proportion of the image rather than in absolute pixels.
- The squircle is the app-icon shape: if the result is going somewhere that already applies its own rounding, exporting a square image is safer — two roundings applied one after the other look wrong.
- Rounding is destructive here: the corners are gone from the file. Where the display can round it instead, a CSS border radius keeps the original intact and adapts to any size.