Free Image to ASCII Art Converter

How It Works

The conversion runs entirely in your browser using the Canvas API — no server, no upload. The tool draws your image onto an offscreen canvas scaled to the target column width, reads every pixel's RGB values via getImageData, and maps each pixel's perceptual brightness to a character from a lookup string you choose.

1. 1
   Canvas scales the image

   Your image is drawn onto a hidden canvas sized exactly to the output grid — typically 80 columns wide by default, with height adjusted automatically to preserve the image's aspect ratio (halved for monospace fonts, which are taller than wide).
2. 2
   Per-pixel luminance sampling

   The tool calls getImageData to read raw RGBA bytes for every cell. It converts each pixel to a single brightness value using the ITU-R perceptual formula (0.299R + 0.587G + 0.114B), then applies your brightness offset, contrast multiplier, and gamma curve.
3. 3
   Brightness maps to a character

   The adjusted brightness (0–1) is multiplied by the length of the chosen character string — standard ( .:-=+*#%@), 70-glyph detailed, block elements, binary, or a custom set you type in — and the character at that index is placed in the output grid.
4. 4
   Export in plain text, PNG, or HTML

   The finished grid is joined into a plain-text string for copy/download. For PNG export, each character is rendered onto a second canvas with fillText at 12px monospace. Color mode reads the original RGB per pixel and wraps each character in an inline-styled span element, which can be exported as a self-contained HTML file.

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