Blur or Pixelate Faces in Your Browser - Step by Step

Last reviewed: 2026-08-23

freetoolonline.com Editorial Team

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This walkthrough covers one full pass through the Face Blur tool: open a photo, let the detector find the faces, choose pixelate or smooth blur, cover anything it missed with the brush, and save the result as a PNG. Every step happens on your own device - the photo is never uploaded.

Check the example before opening anything

When the page loads, a real before-and-after pair is already on screen - a portrait, and the same portrait with the face pixelated. It renders with no clicks and no download, and it is labeled as prepared ahead of time. Ten seconds with that pair tells you what the output looks like before your own picture is involved.

The run, control by control

Step	Control	What happens
1	Choose photo	The image opens on a canvas in the page; it is not sent anywhere
2	Pixelate or Smooth blur	Picks the look: a hard mosaic, or a soft gaussian blur
3	Strength slider	1 to 10 - scales the mosaic block size or the blur radius
4	Blur all faces (AI)	The first click starts a one-time detector download of about 1.3 MB, then every detected face is blurred at once
5	Brush size	8 to 80 pixels, so a licence plate and a whole face both mask cleanly
6	Paint, then Blur painted area	The no-download path: blurs exactly the pixels you painted - plates, tattoos, name tags, missed faces
7	Clear	Wipes the painted mask so you can repaint and try again
8	Download	Saves the edited image as a standard PNG

Step 4 in detail: the one-time download

The face detector is a small on-device model of about 1.3 MB. It is fetched only when you click the AI button, never in the background, and its size is shown before the download starts. Your browser caches it after that first fetch, so blurring a second photo, today or next week, needs no download at all. If you are somewhere without a connection, the brush path still works - it never needs the network.

Steps 5 and 6 in detail: what the brush is for

The detector works above a 70 percent confidence bar, so small, turned-away, or partly covered faces can slip past it. The brush is the designed cover for exactly those, and for everything the detector deliberately does not look for: licence plates, tattoos, name tags, a visible document. Paint the area, click the brush blur, and only the painted pixels change.

Your resolution is not thrown away

Detection runs on a small internal copy of the image, but the blur itself is applied to the full-resolution picture. Everything outside the blurred regions stays pixel-for-pixel identical - a 4000-pixel photo comes back a 4000-pixel photo. The saved file is a PNG re-encoded from the canvas, so the original file's hidden metadata is not carried over.

If a face was missed

That is expected behaviour at the edges, not a failure to work around: the tool tells you when it finds nothing rather than pretending. Zoomed-out group shots, profiles, and faces behind sunglasses or masks are the usual cases. Brush over them - the result is the same blur, applied to exactly the area you chose.

One photo at a time

There is no batch or folder mode, and no video or live camera input; each pass edits a single photo, and nothing is kept once you leave the page. If the person should disappear from the picture entirely rather than be blurred, switch to the Object Remover - that is a different job this page deliberately leaves alone.

Where to go from here

Not sure this is the right tool for the picture in front of you? Blur Faces in a Photo Without Uploading - When To Use It covers the decision. To compare against cloud blur services and manual editing, see In-Browser Face Blur vs Cloud Tools and Manual Editing.

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Last updated: Aug 23, 2026