OneTaskBy Tim King · Updated
Pixelate Image Online
Censor a Face or Mosaic Part of a Photo With a Brush
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How the Pixelate Image works
Pixelate image regions the way TV news hides a face or a number plate: brush over what should be censored and it turns into a mosaic of flat squares. You can also pixelate the whole photo for a retro, low-resolution look.
How to pixelate image areas
Drop a picture in. The tool opens with Apply to set to Brushed areas, so you can paint straight away: press on the preview, drag across the face, plate or text, and let go. The stroke is pixelated as soon as you release, and you can add as many strokes as you need. Double-click the image to clear them all. Strokes are stored relative to the picture, so changing the block size afterwards re-pixelates exactly the same areas.
Choosing the block size
The block size is the width of each square in pixels. Every block is filled with the average colour of the pixels it covers. Small blocks of 6 to 10 px give a gentle mosaic that keeps shapes recognisable; 30 px and above flattens a face on a typical phone photo into a few patches of skin tone. Because the size is in real pixels, a high-resolution photo needs a larger block than a screenshot to look equally coarse.
Whole image and inverse modes
Whole image pixelates everything, which is handy for placeholder art or a deliberately low-res style. Everything except brushed areas does the opposite of censoring: paint over the subject and the rest of the frame turns to blocks, pulling attention to what you kept.
Pixelation and text
Coarse pixelation is a reasonable way to obscure a face, but it is weak protection for text. Characters come from a small alphabet, so the brightness pattern of a pixelated word can be matched against guesses. For passwords, account numbers or addresses, a solid block is the safe choice.
Nothing leaves your device
All processing happens in the browser. The image is never uploaded, and the download is re-encoded from a canvas, so EXIF metadata such as location is removed as well.
FAQ
How do I pixelate just a face in a photo?
Leave Apply to on Brushed areas, set a block size that looks coarse enough, then paint over the face with a brush roughly the size of it. The face is pixelated when you let go of the pointer.
Can pixelation be reversed?
Not exactly, because each block keeps only one average colour. However, for text the averages can be matched against likely words, so use a solid block if hiding characters really matters.
Why does the same block size look different on two photos?
Block size is measured in real pixels. A 4000 pixel wide photo needs much bigger blocks than a small screenshot to look as coarse, because each block covers a smaller share of the frame.
What format is the pixelated image saved in?
It keeps the original JPG, PNG or WebP format and exact dimensions. Anything else, such as HEIC or GIF, is saved as a PNG. Metadata is stripped because the file is re-encoded from a canvas.
See also: all Images tools, Audio, Video & Screen, PDF, SVG, Simulations & Screensavers, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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