About Pixelate
Pixelate replaces each small block of an image with a single average colour, producing the mosaic effect familiar from censored images. The block size is yours to set, and it controls both how coarse the result looks and how much of the original structure survives.
The effect works by shrinking the image down and then scaling it back up without smoothing, so the underlying colours are genuinely averaged rather than merely obscured. That matters when the purpose is redaction: heavy pixelation removes the fine detail rather than blurring it, although the practical protection still depends on the block size being large relative to the feature being hidden.
Two extremes are worth knowing about. A small block size on a small image can produce almost no visible change, since the blocks are close to pixel-sized. A very large block size on a small image collapses the whole picture into a handful of coloured squares, which is a legitimate result but rarely the intended one. Judging the setting on the actual image rather than on the number is the reliable approach.
How to use Pixelate
- 1 Choose the image to pixelate.
- 2 Set the block size in pixels — larger blocks mean coarser output.
- 3 Check the result at full size if it is being used to obscure a feature.
Frequently asked questions
Is pixelation a safe way to hide a face or a number?
It is stronger than blurring, because averaging genuinely removes fine detail rather than smearing it, but the protection still depends on the block size being large relative to the feature. For genuinely sensitive content, cropping the region out entirely is the only method with no residual risk.
Why can I see almost no difference with a small block size?
Because blocks that small are close to the size of the pixels themselves, so there is nothing to average. The effect only becomes visible once the block size is a meaningful fraction of the features in the image.
Does the result keep the original dimensions?
Yes. The image is reduced and then expanded back to the original size, so the output has the same width and height as the input while the content is blockier.
Free, online, and private
Free to use
Pixelate is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.
How Pixelate behaves in detail
These are the specifics of this implementation — the exact ranges, defaults and fixed settings you are working with.
| Parameter | Value |
|---|---|
| Method | two passes — the image is drawn down into a canvas of floor(width ÷ size) by floor(height ÷ size) pixels, then drawn back up to full size with imageSmoothingEnabled switched off |
| Block edge | 2 to 100 px, default 10, floored to a whole number and used as a divisor rather than as an exact block width |
| Output size | the source image's original width and height; the small mosaic is upscaled to fill exactly that frame |
| Output format | always PNG |
Compiled from the implementation of this tool and checked against it by itoolnet.
What Pixelate does not do
Knowing the edges of a tool saves more time than another list of its features. These are the cases where it will not do what you might expect.
- The number you type is a divisor, not the block edge. A 1000 px wide image at size 10 gives 100 columns, and so does a 1003 px one, so the real block is width ÷ floor(width ÷ size) and drifts from the figure you entered.
- Each block is a smoothed average of the pixels underneath rather than one sampled pixel, because the downscale leaves image smoothing on — fine detail inside a block is blended away instead of being picked out.
- The effect covers the whole frame. There is no region select, no choice of block shape, and no way to keep the edges of the picture sharp while the interior is pixelated.
Tested and documented by itoolnet, the team that builds and maintains this site.