Braille to Text Converter

Braille is a tactile writing system encoded in Unicode within the block U+2800 - U+28FF, representing all 256 possible dot combinations in a 2×3 cell. Misreading a single indicator character, such as the number sign ⠼ or the capital sign ⠠, cascades errors through the entire subsequent text. This converter implements Grade 1 (uncontracted) Braille per the Unified English Braille (UEB) standard, processing indicator state machines to correctly resolve ambiguity between letters and digits. It handles bidirectional conversion: paste Unicode Braille to get plaintext, or type plaintext to generate Braille output.

The tool approximates standard Grade 1 transcription. It does not support Grade 2 contractions (e.g., ⠮ for "the") or multi-cell indicators beyond capitalization and number mode. For production transcription of contracted Braille, consult a certified Braille transcriber. Pro tip: when copying Braille from PDF documents, verify that the source uses Unicode Braille rather than a custom font mapping, as font-based Braille will produce garbage output.

Each Braille cell is a 2×3 matrix of dots, numbered:

The Unicode codepoint for a given dot pattern is computed as:

where d_i ∈ {0, 1} indicates whether dot i is raised. The conversion algorithm uses a state machine with two flags:

where capitalNext applies toUpperCase to the next resolved letter, and numberMode remaps cells ⠁ - ⠚ to digits 1 - 0. For the reverse (Text → Braille), the algorithm inserts ⠠ before uppercase letters and ⠼ before the first digit in a numeric sequence.