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How to use Tap Code Translator

Type your text, and the tool converts each letter into its row,column tap-code pair (with K mapped to C) used historically by prisoners to communicate through walls.

Frequently asked questions

What is tap code?

A knock-based cipher on a 5×5 Polybius-style grid where each letter is signalled as a number of taps for the row, a pause, then taps for the column. It was used by American POWs in Vietnam.

Why is there no K?

The 25-cell grid omits K; the letter K is sent using the code for C. When decoding, the C cell always returns C.

How is the output formatted?

Each letter is shown as 'row,column' (for example T = 4,4). You can read each number as that many taps separated by a short pause.

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