PDFConvertersOnline.comHow to pixelate an image
- Choose a picture. Pixelate is already selected.
- Drag boxes or ovals over what you want to cover, or tick Whole image. Move the Strength slider to change the block size.
- Save the picture in its original format and size.
What the mosaic effect does
Pixelation shrinks an area down to a few large squares and fills each square with the average color of the pixels it covers. The result is the familiar blocky mosaic that TV news uses over faces. The Strength slider controls the block size: at low values the blocks are small and shapes stay recognizable; at high values each block covers a big part of the picture and only broad colors remain. Block size is relative to the picture, so a phone photo and a small screenshot get a similar look.
Privacy: when pixelation is enough
For faces, crowds and backgrounds, large blocks work well: a handful of colored squares can't be turned back into a recognizable person. Short text is a different story. A number plate, a phone number or a password on a screenshot comes from a limited set of characters, and people have built tools that pixelate every possible guess and compare it with your mosaic until one matches. Small blocks over small text are the weak spot.
- For faces, use blocks at least as big as an eye.
- For text and numbers, make the blocks larger than the letters, or better, switch the effect to Solid box, which replaces the pixels completely.
- Cover the whole item, including its edges, so no partial letters peek out.
If a soft look suits your picture better than squares, use Blur Image, where the same editor starts with blur instead.
Pixelation as a style
Mosaic isn't only for hiding things. Pixelating the whole picture gives a retro video game feel, a teaser for a reveal post, or a simple abstract background. Tick Whole image, then try a few strengths: mid values keep the outline of a subject, high values leave just color patches. Pixelating one area on purpose, like a gift before its unveiling, is a playful way to build curiosity. Small images with bold shapes, such as logos or icons, give the cleanest pixel-art look, while busy photos turn into soft color fields.
Editing marked areas
Draw as many rectangles or ovals as you need; each can be moved by dragging it and resized from its corners. Use the Brush for irregular shapes. Undo removes the last mark, and Clear all starts fresh. When you save, the mosaic is recalculated on the full-resolution image. Everything outside the marked areas stays untouched, and the file keeps the same format as the original, whether JPG, PNG or WebP.
More ways to use this tool
Frequently asked questions
Can pixelated text be read again?
Sometimes. If the text is short and the blocks are small, someone can try possible words or numbers, pixelate them the same way and find the match. Use large blocks or the Solid box effect for anything that must stay secret.
Can I pixelate only one part of the picture?
Yes. Drag a rectangle or oval over the part you want to cover, or paint it with the brush. Only those areas change.
How do I make the blocks bigger?
Move the Strength slider to the right. The blocks grow with it, and the preview updates right away.
What format is the pixelated picture saved in?
The same as the original: JPG stays JPG, PNG stays PNG and WebP stays WebP. iPhone HEIC photos and AVIF files come out as JPG.
Do you keep a copy of my picture?
No. The mosaic is made inside your browser, and the file never leaves your device.