Free Online Tool
Image Mosaic Tool
Choose a rectangle, circle, or brush selection in a JPG, PNG, or WebP image and apply a mosaic effect before downloading it.
Use Rectangle or Circle by dragging an area, or use Brush to paint over the part you want to hide. Touch is supported on mobile.
Preview zoom
Result preview
Processing Result
The result will appear here.
Selected images are not uploaded to a server and are processed only in your browser.
How to Use
- Select an image file.
- Choose a selection mode. Rectangle and Circle use a dragged area, while Brush lets you paint over the part you want to hide.
- Choose the mosaic block size and brush size if needed.
- Click Apply Mosaic to apply the effect to the selected area.
- Repeat on other areas if needed, then download the result image.
Examples
- Pixelate part of a face with a circular selection
- Hide names, phone numbers, or addresses in a screenshot with the brush
- Pixelate a specific table cell with a rectangular selection
Calculation and Conversion Notes
Image mosaic processing is done by scaling the selected area down on a browser canvas and then scaling it back up to create a pixelated block effect. Rectangle and Circle modes apply the effect to the selected area, while Brush mode uses the painted mask area. Selected images are not uploaded to a server and are processed only in your browser.
FAQ
Is my image uploaded to a server?
No. The selected image is processed only in your browser.
Can I use a circle instead of a rectangle?
Yes. Circle mode pixelates the circular or oval area inside the area you drag.
When should I use Brush mode?
Use Brush mode when the area is irregular, such as around a face outline, a name, or part of an address.
Can I apply mosaic to multiple areas?
Yes. Apply one area, then select or paint another area and apply again.
Can I adjust mosaic strength and brush size?
Yes. Change the block size for mosaic strength, and choose a brush size when using Brush mode.
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