A1Z26 Cipher
Converts text into numbers by each letter position in the alphabet (A=1, Z=26), separated by hyphens. A simple cipher popular in geocaching, escape rooms and logic puzzles.
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A=1 through Z=26, slash for spaces
Scavenger hunt clue, escape room puzzle, geocaching cache: someone hands you a string like 8-5-12-12-15 and the rule is swapping each letter for its position in the alphabet. Type the phrase and the tool returns the numbers separated by hyphens, updating as you write. HELLO becomes 8-5-12-12-15, and OLA MUNDO becomes 15-12-1-/-13-21-14-4-15, with the slash marking where a space sat between words.
The catch is what does not survive. Only letters A to Z go through. Digits, punctuation and accented letters are dropped with no warning on screen. Typing CAFE 2026 ÁGUA returns 3-1-6-5-/-/-7-21-1: the 2026 is gone, the Á is gone with it, and the two slashes from the two spaces ended up side by side. If a number belongs to the clue, spell it out; if a word carries an accent, write AGUA instead of ÁGUA before converting.
The conversion runs one way only, from text to numbers. Reading 8-5-12-12-15 back means counting through the alphabet letter by letter, on paper or in your head. As security it is worthless: numbers between 1 and 26 joined by hyphens are the most recognisable pattern in amateur cryptography, which is why puzzle designers usually stack A1Z26 with a second layer. Everything is computed in the browser and nothing you type is sent anywhere.
Frequently asked questions
How do I decode an A1Z26 sequence?
Why did the numbers I typed disappear?
What about accented letters?
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