A1Z26 cipher
Convert letters to numbers and back with the simple A1Z26 substitution cipher.
A1Z26 cipher
The A1Z26 cipher is a straightforward letter-to-number substitution where A=1, B=2, ..., Z=26. Paste any text and choose to encode (letters to numbers) or decode (numbers back to letters). Each letter becomes its position in the alphabet, separated by your chosen delimiter — by default a hyphen so "hello" becomes "8-5-12-12-15".
Encoding is simple: the tool converts every letter (uppercase or lowercase) to its numeric value, from 1 to 26. Any non-letter character — numbers, punctuation, accented characters, emoji — is dropped during encoding, and word boundaries are marked by spaces. Decoding works in reverse: it reads numbers separated by your chosen delimiter (hyphen, comma, space, or anything else) and converts each back to its letter.
This cipher is purely for fun and basic obfuscation, not cryptographic security. It offers no real protection since the substitution is fixed and obvious. But it is useful for word games, puzzles, encoding messages for friends, or teaching the basics of substitution ciphers. The live tally counts how many letters you have encoded or decoded. Everything runs in your browser, so your text never leaves your device.