Which width should I use for a thermal printer?

58 mm receipt printers are usually 384 dots wide and 80 mm printers 576. Pick the matching width and print at 1:1 so each pixel maps to one print-head dot.

What is the difference between the algorithms?

Floyd–Steinberg gives the smoothest gradients for photos; Atkinson diffuses only part of the error, giving stronger contrast and cleaner areas for portraits and illustrations; Bayer creates a regular grid pattern that looks stylised and suits fast e-ink refreshes.

Are my files uploaded?

No. Everything runs locally in your browser with no network upload, and is discarded when you close the page.

Do I need to sign up or pay?

No. The site is completely free, needs no account, has no usage limits and adds no watermark.

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🏁Image Dithering Online - 1-bit Black & White for Thermal Printers & E-ink

Devices that only print or show two colours — receipt and label printers, e-ink displays, laser engravers — cannot reproduce greyscale photos, and a plain threshold throws away most of the tones. Dithering simulates grey with the density of black and white dots: Floyd–Steinberg is smooth and natural, Atkinson (the classic Mac look) keeps highlights and shadows cleaner, and Bayer ordered dithering gives a regular halftone pattern. Beyond 1-bit black & white you can output 4-level grey, black/white/red for tri-colour e-ink, Game Boy green, or a custom ink and paper colour for two-tone posters. Set the output width to 384 px (58 mm thermal) or 576 px (80 mm thermal) and tune brightness and contrast for the best print.

Free · No sign-up · Runs in your browserLast updated: 2026-10-26

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How to use Image Dithering

1Drop in images
2Choose the algorithm, colours and output width, and tune brightness and contrast
3Click Dither and download the PNG

FAQ

Which width should I use for a thermal printer?: 58 mm receipt printers are usually 384 dots wide and 80 mm printers 576. Pick the matching width and print at 1:1 so each pixel maps to one print-head dot.
What is the difference between the algorithms?: Floyd–Steinberg gives the smoothest gradients for photos; Atkinson diffuses only part of the error, giving stronger contrast and cleaner areas for portraits and illustrations; Bayer creates a regular grid pattern that looks stylised and suits fast e-ink refreshes.
Are my files uploaded?: No. Everything runs locally in your browser with no network upload, and is discarded when you close the page.
Do I need to sign up or pay?: No. The site is completely free, needs no account, has no usage limits and adds no watermark.