A1Z26 Cipher

Each letter is swapped for its number in the alphabet, counting A as 1 through Z as 26. Uppercase and lowercase letters map to the same number, and characters that are not letters, such as spaces and punctuation, are left in place. To encode, type your text on the left and read the numbers on the right. To decode, use the swap button and enter the numbers instead.

Use the separator setting to choose whether the numbers within a word are joined by a space, a dash, or a comma. For example, HELLO becomes 8 5 12 12 15 with spaces or 8-5-12-12-15 with dashes. When decoding, any string of digits from 1 to 26 is turned back into its letter, so the separator you used does not matter.

No. The A1Z26 cipher offers no real security because the mapping is fixed and widely known, so anyone can decode it by hand. It is meant for puzzles, games, and learning how substitution ciphers work rather than for protecting sensitive information. For a shift-based puzzle cipher, try the Caesar cipher tool.