Shapecatcher

Shapecatcher is a web-based Unicode character finder for people who know what a character looks like but not its name or code point. Users sketch a glyph in a drawing box and the tool returns the most similar characters from its database, which currently contains 11,817 glyphs drawn from free Unicode fonts. Chinese, Japanese and Korean characters are not yet supported.

The interface includes draw, fill, erase and clear tools, with recognition triggered after the sketch is complete. The matching engine uses shape contexts, a mathematical descriptor of shape similarity, and runs on CUDA-accelerated NVIDIA graphics hardware to speed up comparisons. The site is available as a free web tool; no paid editions, trials or seat-based plans are described.