Turn a photo into a Voronoi mosaic
This tool covers your picture with Voronoi cells and paints each cell with the average color of the pixels inside it. The result looks like stained glass or a low-poly illustration: the shapes simplify the image, but the colors and light are kept.
- Choose a photo or drop it on the preview. The demo picture loads by default.
- Set the number of cells — fewer for an abstract look, more to keep detail.
- Pick a placement: Random for a natural, uneven look, Even for cells of similar size, or Detail to concentrate cells on edges.
- Add a border for a stained-glass effect, and use Compare with original to check the result.
How the colors are computed
The image is scaled to at most 900 pixels on its long side. For every pixel the tool finds the nearest cell site — that is the definition of a Voronoi cell — and adds the pixel's color to that cell's total. Each cell is then filled with the average. Detail placement first measures how quickly brightness changes across the image and samples sites more densely where it changes fast.
For a dot-based version of the same idea, try Voronoi stippling. To design an abstract pattern instead of following a photo, use the Voronoi pattern generator.
Frequently asked questions
Is my photo uploaded to a server?
No. The image is read and processed entirely in your browser. Nothing is sent anywhere.
What does Detail placement do?
It puts more cells where the image has edges and texture, such as faces, outlines and lettering, and fewer cells in flat areas like sky. Faces and objects stay recognizable with far fewer cells.
How many cells should I use?
A few hundred cells give a bold, abstract look. Two to five thousand keep most of the picture's detail. Detail placement needs fewer cells than random placement for the same result.
Why are some cells colored differently from what I expect?
Each cell gets the average color of every pixel inside it. A cell that crosses an edge between a dark and a light area will show a blend of the two.