Does the output resolution change?

No. The image is downscaled internally and upscaled back to the original dimensions with nearest-neighbor sampling, so the pixel size stays the same.

What does quantization actually do?

Each RGB channel snaps to a fixed number of evenly spaced levels, which collapses similar colors into a small palette.

Yes — everything runs on canvases in your browser tab.

Nearest-neighbor upscaling deliberately skips smoothing; that is what gives pixel art its crisp squares.

Image Tools100% Private · In-Browser

Turn photos into chunky retro pixel art with a block-size slider and optional color posterizing — crisp nearest-neighbor blocks, zero uploads.

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Block size slider from 2 to 64 px controls how coarse the mosaic is.
Optional color quantization posterizes each channel to 2–16 levels for a limited-palette, 8-bit feel.
A downscale-then-nearest-neighbor-upscale pipeline keeps the blocks razor sharp.
Output keeps the original pixel dimensions — the look changes, the size does not.
Live stats show blocks across and down, and the preview renders with pixelated rendering.

Drop In Your Image
Any photo or graphic works as the source.
Drag The Block Size
Small values give a subtle mosaic; large ones go full retro.
Optionally Quantize
Flip the switch and pick levels per channel to flatten the palette further.
Save The Pixelated PNG
Exported at full resolution with hard-edged blocks.

8–16px blocks are a good retro range for typical photos.
Quantization at 3–5 levels per channel delivers the strongest old-school game look.
Blocks also obscure detail — handy for censoring faces or license plates before sharing.

Image, PDF, text, calculator and media utilities — all free, all private, all running right in your browser.