What is Pixelate Image?
Pixelating an image replaces detail with large square blocks, each filled with the average colour of the pixels it covers. It is the mosaic effect used to hide faces, plates and documents, and the stylised look used in retro covers and thumbnails. Unlike a blur, a pixelated image keeps hard edges between blocks - the result is readable, printable and does not look soft. This tool does the work locally in your browser: pick a block size, watch the preview update, and download the PNG.
Common Uses for Pixelate Image
- Hide a face, badge or number plate before posting a photo
- Mask a document or screenshot in a tutorial
- Make mosaic-style covers and thumbnails
- Create a blocky retro version of a logo or photo
- Reduce an image to a simple, printable colour pattern
Choosing a block size
Small blocks (4-8 px) keep the image recognisable and give a subtle retro texture. Medium blocks (12-20 px) read clearly as a mosaic. Large blocks (24-32 px) turn the image into an abstract pattern of colour, which is what you want for strong redaction. The preview updates instantly, so the fastest way to choose is to step up until the detail you care about disappears.
Pixelation versus posterising
Two settings control the look. The block size sets how coarse the grid is; the colour count sets how many distinct colours remain. For true redaction and mosaic effects, keep the colour count high so each block keeps its own hue - lowering the colour count merges similar blocks and produces a flatter, poster-like image instead of a mosaic.
Common mistakes with redaction
The two classic failures are drawing a translucent brush over a face and lightly blurring text. Both leave enough signal to reconstruct. Pixelating at a sufficient block size is the safer default, and it is worth checking the exported file at 100% rather than relying on a small preview: numbers and faces that look gone in a thumbnail can survive at full size.