How to blur or pixelate faces in a photo

Hide faces and license plates in six steps

1. 1

   Open the photo

   Go to lilcactus.app and choose File› then Open…, or drag the photo onto the window. To follow along exactly, open the sample photo from this page.

2. 2

   Select the faces

   Press M for the Marquee Select tool (or right-click the selection button in the toolbar and choose it) and set Shape to Ellipse on the options bar. Choose View› then Zoom In two or three times, until each face is about the size of a coin on the screen. Scroll, or hold Space and drag, to bring each face into view before you draw around it. Drag an oval around the first face, from above the hair to below the chin. Then hold Shift or ⇧, start the next drag, and let go of Shift or ⇧: each new oval is added to the selection. Circle all three faces, and include anything else that identifies a person, such as distinctive hair, clothing or a reflection.

   

3. 3

   Pixelate the faces

   Choose Filter› then Pixelate› then Pixelate… Cell Size sets the size of each block. Use about a fifth of the widest face’s width, so each face is only a few blocks across: these faces are 40 to 65 px wide, so type 14 and press Tab. Click Apply. Only the selected ovals change. For a face that fills much of the photo, cover it instead, as below.

   

   

   

4. 4

   Blur the license plate

   On the options bar, set Shape to Rectangle and drag a rectangle over the plate, keeping it on the plate’s white border; a new drag replaces the face selection. Choose Filter› then Blur› then Gaussian Blur…, type 12 for Radius, press Tab and click Apply. The letters turn into soft gray shapes that can’t be read. Go by the letter height: these letters are about 30 px tall, and a Radius of 8 still left them readable, so use at least 40% of the letter height. A blurred or pixelated plate can still be worked out by blurring candidate plates the same way and comparing, so to hide a plate for sure, fill it instead with Edit› then Fill with Foreground.

   

   

5. 5

   Check at 100%

   Choose Select› then Deselect, then View› then Actual Size (100%) and look at each area. Nobody should be recognizable and no letter readable. If something still shows through, select that area again and apply the filter again with a bigger Cell Size or Radius. Don’t undo back to it: undoing an earlier step also undoes everything you did after it, such as the plate blur.

6. 6

   Export without location data

   Choose File› then Export› then JPEG… Photos from phones often carry the place and time they were taken; set Image metadata to None so the copy leaves them out. Type a new File name, such as street-faces-hidden, so you can’t mix the two up, then click Export. Share the exported copy and keep the original private. File› then Save would instead write the hidden version back into the JPEG you opened.

   

   

Pixelate, blur or cover?

• Pixelate makes it obvious that something was hidden, and with big blocks little detail is left.
• Blur looks softer and suits backgrounds, signs and screens that don’t need to stay secret.
• Cover with a solid color leaves nothing at all: select the area and choose Edit› then Fill with Foreground, which fills it with the foreground color (black unless you changed it). Use it for documents, ID cards and anything that must not be recovered.

Fix common problems

The whole photo was pixelated

Nothing was selected when you chose the filter. Choose Edit› then Undo, select the faces and apply it again.

The edge of a face still shows

The oval was too tight. Draw a larger oval around it, with a margin around the hair and chin, and apply the filter again.

Pixelate is grayed out

The active layer is locked or isn’t an image layer (for example, a text or adjustment layer). Unlock it in the Layers panel, or click the photo’s row, then try again.

Coming from another editor

Photoshop

Select the area, then Filter › Pixelate › Mosaic… or Filter › Blur › Gaussian Blur…

GIMP

Select the area, then Filters › Blur › Pixelize… or Filters › Blur › Gaussian Blur…

Blurring faces: questions and answers