Image to Braille Art

2×4 dots per character · dithering · copy as text

Braille characters are the highest-resolution text art available in Unicode. Each one is a 2×4 grid of independently addressable dots, so a single character carries eight pixels where an ASCII character carries one brightness level — four times the vertical detail of conventional ASCII art, in the same number of columns.

Why dithering matters more here than in ASCII art

ASCII art has a built-in grey scale: @ is dark, . is light, and a good ramp gives you ten or more levels per character. Braille has none of that — a dot is either raised or it is not. Every pixel is forced to pure black or pure white, which is a one-bit quantisation of an eight-bit image.

Straight thresholding at one bit produces posterised blobs: any gradient collapses into a hard edge wherever it crosses the threshold, and a whole face can become a silhouette. Floyd–Steinberg dithering fixes this by pushing each pixel's rounding error onto its neighbours, so a mid-grey region becomes a stipple of roughly half-on dots that reads as mid-grey from a distance. Leave it on for photographs. Turn it off for line art, logos and text, where the crisp edges are the whole point and a dither just adds noise.

Picking a width

The width is in characters, and each character is two dots wide, so 80 columns samples the image at 160 pixels across. That is a good default: it fits an 80-column terminal, a Discord message and most code comments. The height follows automatically from the aspect ratio — because braille cells are two dots wide by four tall while a terminal cell is roughly twice as tall as it is wide, the two distortions cancel and the picture comes out with correct proportions.

Beyond about 120 columns you are past the width of most places you would paste this, and the lines wrap into unreadability. Below about 30 the subject stops being recognisable. If the result is muddy, try raising the threshold before increasing the width — often the image is simply too dark rather than too small.

FAQ