How Pixelation Hides Detail in an Image
Pixelation trades detail for blocks, and the block size decides how much is lost.
What is the Pixelate Image Tool?
Pixelation groups pixels into blocks, and larger blocks hide more detail. The tool divides your image size by the block size, rounding up, so the block count is exact. In the browser a gradient preview is shrunk and enlarged without smoothing to show the effect, which you can download. It is a visual effect, not a guarantee that hidden detail can never be recovered, so do not rely on it for sensitive information.
How to use it
- Enter the image size and block size
- Check the block count
- Preview the pixelated effect and download it
Worked example
A 16-pixel block on a 400 by 300 image gives 25 blocks across, 19 blocks down and 475 blocks in total.
How big should pixel blocks be?
Small blocks keep the picture readable, while large blocks hide faces and text. The right size depends on what you need to hide and how the image will be viewed.
Frequently asked questions
Does pixelation make a face unrecognisable?
Larger blocks hide more, but pixelation alone is not a safe way to hide sensitive detail, since the original may still exist elsewhere.
Why round the block count up?
Because a partial block at the edge still counts as a block, so the total covers the whole image.