Sharpening a pixelated image, which hardens the block edges instead of hiding them.
Resolution and scaling
Pixelation
Also called pixelated image, blocky image or pixellation. Here is what it means, when it changes what you export, and what people get wrong.
Resolution and scalingRuns on your deviceUpdated 10 August 2026
The short answer
Pixelation is when individual pixels become visible as square blocks because an image is shown larger than its pixel count supports. It is not damage to the file: the pixels are being stretched across more space than they were meant to cover. The only true fix is more pixels.
Updated
The short version
Pixelation at a glance
| Quick fact | Detail |
|---|---|
| Cause | Display size exceeds available pixels |
| Block size | Matches the enlargement factor |
| Not the same as | JPEG blocking, fixed at 8 x 8 pixels |
| Real fix | A higher-resolution source file |
| Partial fix | Learned upscaling, which estimates detail |
| Makes it worse | Sharpening, and nearest-neighbour enlargement |
Slide the table sideways to see every column.
What causes an image to pixelate?
Four situations account for nearly all of it. Displaying or printing an image beyond its native resolution, so each pixel occupies a visible area. Enlarging with nearest-neighbour interpolation, which replicates pixels into hard squares rather than blending them. Starting from a low-resolution source, such as a thumbnail lifted from a web page or a screenshot of a photo. And deliberate pixelation, applied as a privacy filter to hide a face, a name or an address.
How do you tell pixelation from JPEG blocking?
They look similar and need opposite fixes.
- Pixelation: blocks are all the same size, their size matches the enlargement factor, edges are perfectly sharp, and the effect is uniform across the whole frame including flat areas.
- JPEG blocking: blocks are fixed at 8 x 8 pixels on the original grid, so they stay small however much you enlarge. They are worst in smooth gradients such as skies and white backgrounds, and are often accompanied by mosquito noise, a faint shimmer around high-contrast edges.
Pixelation means you need a bigger source. Blocking means the file was compressed too hard, and the fix is to re-export from the original at a higher quality setting. Re-saving a blocky JPEG at quality 100 achieves nothing, because the damage is already baked into the pixels.
Can a pixelated image be repaired?
Start by hunting for the original. A pixelated file is usually a small copy of something larger that still exists on a phone, in an email attachment or on a supplier's site. That search is worth ten minutes before anything else.
If there is genuinely no original, a learned upscaler will smooth the blocks and reconstruct plausible edges, which looks considerably better than blurring and is often enough for a listing thumbnail. It is estimation, not recovery, so check any text, pattern or face closely before publishing. Sharpening a pixelated image is the one thing that reliably makes it worse, since it hardens the block boundaries you were trying to hide.
What people get wrong about pixelation
Each one is a real failure mode, not a style preference.
Assuming the file is corrupt when it is intact and simply too small for the size it is being shown at.
Re-saving a blocky JPEG at maximum quality and expecting the blocks to lift, when the artefacts are already in the pixel data.
Trusting light pixelation to hide a name or address, since coarse blocks are safer and weak ones can sometimes be undone.
Questions people ask
Pixelation, answered
The follow-up questions people search for once they have the definition.
How do I unpixelate a photo?
There is no true reversal, because the detail was never in the file. Find the original first. Failing that, a learned upscaler can rebuild plausible edges and texture, which usually reads far better than the blocks. Verify any text or faces before you use the result.
Why does my logo look pixelated on my website?
The raster file is smaller than the space it is being drawn into, and high-density screens double the demand by rendering roughly two device pixels per CSS pixel. Export the logo at twice its display size, or use SVG, which stays crisp at any size.
Does zooming in cause pixelation?
Yes, once you pass 100 percent. At 100 percent one image pixel maps to one screen pixel. At 400 percent each image pixel covers a 4 x 4 area of the display, so it becomes a visible square. The file has not changed, only how it is being shown.
Is pixelation the same as blurriness?
No, and the difference points to the cause. Pixelation gives hard-edged squares and comes from too few pixels. Blur gives soft, gradual transitions and comes from missed focus, camera shake or over-aggressive smoothing. An image can suffer from both at once.
Same cluster
More from the glossary
Neighbouring entries, so every term in the set is one hop from every other.
PNG
PNG (Portable Network Graphics) is a lossless image format that stores every pixel exactly as it was saved and supports full alpha transparency.
PPI
PPI, pixels per inch, states how many image pixels are packed into each inch of output.
PDF image
A PDF image is a picture placed inside a PDF page rather than an image format in its own right.
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