The A1Z26 system
Each letter is replaced by its position in the alphabet: A=1, B=2, C=3 … Z=26. So "CAT" becomes 3-1-20. It is one of the oldest simple substitution ciphers and a staple of puzzle hunts and escape rooms. Choose your separator (space, dash or none) and direction above; spaces between words are kept as word breaks in number mode.
Frequently Asked Questions
What number is the letter M?
13 — M is the 13th letter of the alphabet.
Can I decode numbers back to letters?
Yes — switch the direction to "Numbers to Letters" and paste a sequence like 8 5 12 12 15 to get HELLO.
Related Tools
Length Converter — Convert cm to inches, feet to meters, km to miles and more — instantly.
Weight Converter — Convert kg to lbs, grams to ounces, stones to kg and more.
Temperature Converter — Convert Celsius to Fahrenheit and Kelvin — weather, cooking and science.
Volume Converter — Convert liters to gallons, ml to cups, quarts, pints and cubic feet.
Time Converter — Convert hours to minutes, days to hours, weeks, months and years.
Data Size Converter — Convert MB to GB, GB to TB, bits and bytes — KB vs KiB explained.
Number System Converter — Convert binary, octal, decimal, hex and ASCII text — all at once.
Number to Words Converter — Write numbers in words for cheques and documents — and words back to numbers.
Percent to Decimal Converter — Convert percent to decimal and fraction — all three forms at once.