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Dither Image

Dithering fakes shades that a limited palette cannot show by scattering the colours it does have. Floyd-Steinberg does this by quantising each pixel, then pushing the rounding error onto neighbouring pixels, so from a distance the speckle reads as the original tone.

Image
Drop an image here or click to browse
or paste from clipboard (Ctrl+V) · JPEG, PNG, WebP
Files stay in your browser. Nothing is uploaded.

How to dither an image online

  1. Add your image

    Drop a JPG, PNG or WebP onto the drop zone, or click to pick one.

  2. Choose the levels

    Two levels per channel gives the classic 1-bit look. Four, eight or sixteen keep progressively more tone.

  3. Pick colour or mono

    Leave black and white on for the newspaper and e-ink look, or turn it off to dither each colour channel separately.

  4. Download the result

    The preview updates as you change settings. Download it as a PNG when it looks right.

Why use this tool

Real error diffusion

Uses the Floyd-Steinberg kernel rather than a fixed pattern, so gradients break into fine speckle instead of visible banding.

Five depth settings

From 2 levels per channel for a hard 1-bit result up to 16 levels, where the effect becomes a subtle texture.

Colour or black and white

Mono collapses to luminance first for the classic look, while colour mode dithers each channel and keeps hues.

Always saved as PNG

Lossy compression would smear the speckle the moment it was applied, so the output is always lossless.

Runs entirely in your browser

Your image is never uploaded.

About this tool

Dithering is what you do when you have fewer colours than the picture needs. Instead of rounding every pixel to the nearest available colour and producing ugly bands, you round it and then carry the leftover error into the pixels you have not drawn yet. Those neighbours get nudged slightly lighter or darker to compensate, and the resulting speckle averages out to the tone that was lost. Stand back and your eye does the blending.

The Floyd-Steinberg kernel used here spreads that error across four neighbours, seven sixteenths to the pixel on the right and the rest onto the row below. It became the default because it is cheap and because the noise it produces is fine and unstructured rather than the crosshatch you get from ordered patterns. Two levels per channel gives the pure black-and-white look of early Macintosh screens and newspaper wire photos. Higher settings keep more tone while still adding visible grain.

Black and white mode collapses the image to luminance before quantising, which is the version most people are after. Turning it off dithers red, green and blue separately, so colour survives but is reduced to a small palette, closer to how old indexed-colour formats looked. Output is always PNG because saving dithered pixels as a lossy format would blur exactly the fine detail the process just created. For related effects there is pixelate image, grayscale image, and image to ASCII.

Frequently asked questions

What is image dithering?
A way of showing more apparent shades than your palette actually contains, by scattering the available colours in a pattern that averages out to the tone you wanted. It is why a black-and-white newspaper photo can look like it has grey in it.
What does 1-bit mean?
One bit per pixel, so every pixel is either black or white with nothing in between. Selecting 2 levels with black and white on produces exactly that.
Why is the download always a PNG?
Because dithering creates deliberate single-pixel detail, and lossy compression is designed to throw that away. Saving as JPG would blur the speckle into grey mush and often make the file larger.
Why does the result look grey when I zoom out?
That is the effect working. Your eye is averaging the black and white pixels into a mid tone, which is the whole point of error diffusion.
Does it work on large images?
Yes, though very large files are scaled down first to stay within the browser canvas limit. A note appears under the result when that happens.
Is my image uploaded anywhere?
No. Everything runs in your browser and the image never leaves your device.

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