Pixelate an image

Turn a photo into big mosaic blocks, or pixelate only the parts you mark, without sending it anywhere.

Drop an image to pixelateor click to choose a file.

    For text such as card numbers or addresses, use Black box: blurred or pixelated text can sometimes be read back.

    Working…

    Done

    Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.

    Pixelating replaces each square block of an image with the average colour of that block. It is the mosaic effect TV news uses on bystanders, and the look behind pixel-art avatars and retro posters. This page opens set to pixelate the whole picture, so you see the effect the moment the image loads; drag the Strength slider to make the blocks bigger or smaller.

    To pixelate only part of a picture, switch Hide to "Areas I mark" and drag a box over each face, logo or name. Every box gets the same block size, and the preview redraws as you go, so you can check nothing is still recognisable before saving. Strength is measured against the size of the image, which means a strength of 5 gives the same chunky look on a 600 pixel screenshot as on a 12 megapixel phone photo.

    A word of caution for text. Light pixelation of a few words can sometimes be reversed: tools exist that render candidate text, pixelate it the same way, and compare. For account numbers, passwords and addresses use a large block size or, better, the Black box effect, which leaves nothing behind.

    The mosaic is computed on a canvas inside your browser tab. The picture is never uploaded, the saved file is written fresh from the canvas without its camera or location metadata, and the page keeps working with Wi-Fi switched off.

    How it works

    1. Drop a photo or screenshot, or tap to pick one. The whole picture is pixelated straight away.
    2. Set the block size with Strength. To pixelate only faces or text, choose "Areas I mark" and drag a box over each one.
    3. Save the image. It downloads at full resolution in the format you picked.

    In your browser, not on a server

    Your browser decodes the photo (libheif or the Squoosh decoders step in for HEIC, AVIF and JPEG XL) and draws it on a canvas in your tab. Each area you mark is pixelated by averaging blocks of pixels, blurred by three passes of a box blur that reads the pixels around the area so the edge blends in, or filled with solid black. The same code draws the preview and the full-size file, which is encoded once in the format you chose. Find faces runs Google’s MediaPipe face detector (Apache-2.0) as WebAssembly in your tab, loaded from this site only when you press the button.

    Compared with upload-based tools: The photos people blur are the ones that should not be uploaded: a child’s face, a car’s number plate, a bank screenshot, an ID card. Online blur tools and editors take the unblurred original onto their server first, and several ask for an account before the download. Here the original never leaves your device.

    Verify it yourself. Load this page, turn off Wi-Fi or switch to airplane mode, and run the tool. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.

    Questions

    How do I pixelate only a face?

    Choose "Areas I mark" under Hide, then drag a box over the face. Add a box for every face you want hidden; tap Γ— on a box to remove it. The rest of the photo stays sharp.

    What block size hides a face?

    A face should be covered by no more than about 6 to 8 blocks across. If you can still tell who it is in the preview, raise Strength. For small faces in a group photo, the default is usually plenty.

    Can pixelation be undone?

    The saved file holds only the averaged blocks, so the original detail is gone from it. What can sometimes be guessed is short text under small blocks, by matching candidates. Use Black box for sensitive text.

    Is the file uploaded anywhere?

    No. There is no server in this process. The page is a static file and the work is done by code running inside your browser tab. You can load the page, turn off Wi-Fi, and it still works.

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