Encoding

Convert letters to their alphabet position numbers (A=1…Z=26) and back.

Encrypt/decrypt with the affine cipher E(x)=(a·x+b) mod 26, including key validity checks.

Convert text to ASCII/Unicode code point numbers and convert numeric lists back to text.

Convert text between ASCII/Latin-1 and IBM EBCDIC code pages, byte for byte.

Encode and decode text using Ascii85 (Adobe variant).

Encode or decode text with the Atbash cipher, mirroring each letter to its opposite in the alphabet.

Encode text to Baconian 5-bit A/B groups and decode it back.

Encode text to uppercase Base16 (RFC 4648 hex) and decode it back, with strict validation.

Encode text to RFC 4648 Base32 and decode it back.

Encode/decode using the RFC 4648 Base32hex extended-hex alphabet (0-9A-V).

Convert between arbitrary-length integers and Base36 (0-9, a-z) strings.

Encode text to RFC 9285 Base45 or decode Base45 back to text, as used in QR-code data payloads.

Encode bytes/text to Base58 (Bitcoin alphabet) and decode it back.

Encode bytes or big integers to Base62 (0-9A-Za-z) and decode back, like short-URL IDs use.

Decode a Base64 or data: URI image string and report its real format, dimensions, and size.

Directly transcode between Base64 and Base32 representations of the same bytes without manual decode/encode.

Encode text to Base64 (standard or URL-safe) and decode it back — live.

Wrap Base64 content into a data: URI with a chosen MIME type, or extract the MIME and decoded payload from an existing data URI.

Convert between Base64-encoded data and its hexadecimal byte representation in both directions.

Encode or decode text using the URL-safe Base64 alphabet with optional padding for tokens and URLs.

Encodes and decodes data across Base85 alphabets: ASCII85, RFC 1924, and Z85 side by side.

Encode binary text to basE91, a denser ASCII encoding than Base64.

Encrypt and decrypt with the reciprocal Beaufort polyalphabetic cipher.

Convert printable text to and from Unicode Braille patterns (Grade 1).

Encode or decode text with a configurable Caesar shift, rotating letters by any amount while preserving case and symbols.

Show every character's value simultaneously in decimal, binary, octal, and hex.

Convert Unicode code points to their UTF-8 and UTF-16 byte encodings and back.

Encrypt/decrypt with a keyword-based columnar transposition cipher.

Escape a single value for safe CSV embedding (RFC 4180 quoting) and unescape a CSV field.

Encode text into flag-semaphore positions and visualize the two-flag clock angles.

Encrypt and decrypt digraphs using the classical four-square cipher.

A Vigenere variant that uses a numeric key instead of a keyword.

Compress text with gzip and output Base64, or decode Base64 gzip back to the original text.

Convert text to hexadecimal and back, with optional uppercase.

Escape text to HTML entities and unescape entities back to text.

Convert between HTML named entities (&) and their numeric forms (&/&) both ways.

Escape arbitrary text into a safe JS string literal and unescape it back.

Encode and decode JSON Pointer reference tokens with the ~0/~1 escape rules.

Decode a JSON Web Token into its readable header and payload claims, with human-friendly timestamps for exp/iat/nbf.

Reference of Morse prosigns, Q-codes, and common abbreviations beyond plain letters.

Translate to Morse with selectable dot/dash glyphs and standard PARIS timing breakdown.

Encrypt and decrypt using the Polybius-square plus additive-key Nihilist cipher.

Convert text into numeric HTML character references (decimal or hex) and decode them back to plain text.

Encode UTF-8 text to space-separated octal byte values or decode octal numbers back into readable text.

Searchable table of percent-encoded (%XX) values for ASCII and common reserved characters.

Encrypt and decrypt with the classic 5x5 Playfair digraph substitution cipher.

Encode/decode text using a 5x5 Polybius square coordinate cipher.

Convert internationalized domain names to ASCII Punycode (xn--) and back to their Unicode form.

Encode text to MIME quoted-printable or decode quoted-printable email content back to text.

Encrypt and decrypt text with the zigzag rail fence transposition cipher.

Escape text so it matches literally inside a regular expression, for several flavors.

Apply a Caesar-style rotation with any shift 0-25, with brute-force preview of all shifts.

Safely quote text as a single shell argument for POSIX sh/bash or PowerShell.

Cheatsheet of phonetic/spelling alphabets across NATO, LAPD, and aviation use.

Escape text into a safe SQL string literal for common database dialects.

Encode/decode text to the tap code used as a 5x5 grid of knocks.

Convert text to its binary (and back), with a configurable separator.

Detect and normalize visually deceptive lookalike characters in text.

Convert characters to \uXXXX escape sequences or unescape them back to readable Unicode text.

Apply and compare the four Unicode normalization forms to text.

Expand RFC 6570 URI templates with variables, applying correct percent-encoding per operator.

Percent-encode and decode text or whole-component URL strings.

Compare and apply the three JavaScript URL-encoding functions side by side on the same input.

Show the UTF-16 code units (and surrogate pairs) for text and convert hex code-unit lists back into characters.

Break text into its UTF-8 byte sequence with per-character hex, binary, and code points.

Encode and decode data in the classic Unix uuencode format.

Encodes and decodes data using classic Unix uuencode and xxencode formats.

Encrypts and decrypts text with the autokey variant of the Vigenere cipher.

Encrypt or decrypt text with a repeating-key XOR cipher, outputting or reading hex or Base64.

Encode and decode using the XXencode alphabet (a safer uuencode variant).

Encode/decode using ZeroMQ Z85, a printable Base85 variant safe for source code.

Hide a secret message inside cover text using invisible zero-width characters, and extract it.