Your friend for ciphers.

Shift each letter by a fixed amount.

Caesar with shift 13. Encoding and decoding are the same operation.

Mirror the alphabet — A↔Z, B↔Y, C↔X, and so on.

Polyalphabetic shift — each letter moves by the matching letter of a repeating key.

Write the message in a zigzag across N rails, then read off rail by rail.

Linear substitution: y = (a·x + b) mod 26. Caesar is the special case where a = 1.

Each letter as a 5-bit A/B pattern. The first ASCII-style binary, from 1605.

Each letter encoded as its (row, column) in a 5×5 grid. I and J share a cell.

Each letter as two clusters of taps — row count, then column count. C and K share a cell.

Pack arbitrary bytes into the printable subset of ASCII.

Bytes as base-16 digits, two characters per byte.

Percent-encode characters that would break a URL.

Bytes as 8-bit binary, space-separated.

Tactile script for the visually impaired. Six-dot patterns per letter (Grade 1).

One-way 256-bit cryptographic hash. Same input always yields the same digest.

Modern authenticated encryption. AES-256 + PBKDF2-derived key from your passphrase.

Dits and dahs. Letters separated by spaces, words by " / ".

Read the input backwards. The simplest possible cipher.

aLtErNaTiNg cAsE — encode and decode are the same operation.

Substitute letters with lookalike digits. h3110 fr13nd.

Spell each letter as its phonetic word: Alpha, Bravo, Charlie…

Move the leading consonants to the end and add "ay". Vowel-starts get "way".

Count how often each letter appears and compare to the English baseline.