How to Pixelate an Image
Most people reaching for a pixelation tool want to censor something specific — a face, an address on a form, an account number in a screenshot — and applying the effect to the entire photograph is useless for that. So region mode is the default here: drag the box over what needs covering, resize it with the corner handle, and only that area is broken into blocks while everything else stays perfectly sharp. The pixelation itself is real block averaging rather than a blur dressed up to look blocky. Each block is set to the average colour of every pixel it covers, which is what produces the clean hard-edged squares people recognise as a deliberate censor mark, and it's the honest way to do it. Block size scales with the image, so the same setting looks proportionally similar on a phone screenshot and a full-resolution photograph. One caution worth stating plainly: fine pixelation applied to text is not reliable protection, because each small block still carries a distinguishable average that can, with effort, be worked backwards. For anything genuinely sensitive, use large blocks so entire words collapse into a handful of flat squares. Batch a folder with the same settings and take the results as one ZIP. Nothing is uploaded.
Add your images
Drag and drop, paste, or click to browse — multiple at once.
Position the region
Drag the box over what needs censoring, then set the block size.
Download
Save each image, or take the whole batch as one ZIP.
How Block Averaging Works
Shrink, then enlarge without smoothing
The area is scaled down so each block becomes a single pixel carrying the average of everything beneath it, then scaled back up with smoothing switched off. That's what produces flat squares with hard edges rather than a soft gradient.
Why block size decides everything
Small blocks preserve the overall shape of what's underneath, which is why a lightly pixelated word can still be guessed. Large blocks collapse whole features into a few flat colours, and at that point the information really is gone.
Common Use Cases
Censor a face
The classic use — obvious, deliberate and effective at large block sizes.
Hide account details
Cover a card number or reference in a screenshot.
Redact a document photo
Obscure names and addresses before sharing.
Number plates
Censor a registration in a vehicle photo.
Retro pixel art look
Pixelate the whole image for a deliberately low-res aesthetic.
Anonymise screenshots
Share a UI bug without exposing customer data.
Spoiler covers
Pixelate part of a thumbnail so it doesn't give the ending away.
Mosaic thumbnails
Create an abstract placeholder from a real photo.
Tips & Best Practices
Use large blocks for censoring
If individual letters are still distinguishable as shapes, the blocks are too small to protect anything.
Extend past the edges
Cover a little more than you need — partial detail at the boundary can reveal what's underneath.
Check at full resolution
Something unreadable in a small preview may be perfectly legible when zoomed in.
Prefer pixelation when intent matters
Blocks read unmistakably as deliberate censorship, where a blur could be mistaken for a camera effect.
Never redact inside a document
Covering text in a PDF or slide leaves the original underneath. Export a flattened image instead.
Pixelate before compressing
Do the censoring first, then compress the final image once.
Troubleshooting
I can still make out the text
The blocks are too small. Increase the block size until whole words collapse into a few flat squares.
The blocks look soft, not sharp
That shouldn't happen here — this uses true block averaging with smoothing disabled. If the image was already blurry, that softness comes from the source.
The region misses on some images
The position is a percentage applied to every image, so it only lines up if the subject sits in the same place across the batch.
The whole image got pixelated
Whole-image mode is selected. Switch to region mode and position the box.
Frequently Asked Questions
How do I pixelate an image for free?
Drop your images above, drag the region over what needs censoring, set the block size and download — free, no signup.
Can I pixelate just part of an image?
Yes, and it's the default. Drag the box over the area and only that is pixelated.
Are my images uploaded to a server?
No. Pixelation happens entirely in your browser, which matters when you're censoring something sensitive.
Is pixelation safe for hiding information?
At large block sizes yes. Fine pixelation of text can sometimes be reversed, so use chunky blocks for anything sensitive.
Should I use blur or pixelation?
Pixelation reads unmistakably as deliberate censorship; blur looks more natural. Both are effective at high strength.
How do I censor a face?
Position the region over the whole head, extend a little past the edges, and use a large block size.
What block size should I use?
For censoring, large enough that no feature or letter remains distinguishable. For a retro look, whatever you like.
Can I pixelate several images at once?
Yes, though in region mode the same position applies to all of them.
How does pixelation actually work?
The area is scaled down so each block becomes one averaged pixel, then scaled back up with smoothing off — producing flat, hard-edged squares.
Can pixelation be reversed?
Fine pixelation of known text sometimes can, because each block still carries a distinguishable average. Large blocks destroy the information.
Why not just draw a black box in a document?
Because the original data usually remains underneath and can be recovered. A flattened image has no such layer.
Is there a file size limit?
No. Nothing is uploaded, so the only constraint is your device's memory.
Which format should I choose?
PNG keeps the hard block edges perfectly crisp. JPEG can soften them slightly but gives a smaller file.
Can I undo the pixelation?
Not from the saved file — that's the point. Keep your original if you might need it.
Does it remove EXIF data?
Yes. Canvas-based processing drops metadata, including any GPS coordinates.
Does it work offline?
Once the page has loaded it runs entirely in your browser, so it keeps working without a connection.
Does it work on phones?
Yes, in any modern browser on Windows, Mac, Android or iPhone with nothing to install.
Is this tool really free?
Completely free, forever — no account, no ads and no premium wall.
100% free · No signup · Processed in your browser · Never uploaded
Last updated: September 2026 · FlipMyFormat Pixelate Image
Written and maintained by the FlipMyFormat team · Runs entirely in your browser