Crypto & Security Tools
Classic ciphers to encode and decode (Caesar, XOR, book cipher and more), plus practical security helpers: identify a hash type, check a Luhn or ISBN digit, measure string entropy and generate API keys. Everything runs locally, so secrets never leave your browser.
XOR Cipher
Free XOR cipher tool: encrypt text to hex with a repeating key and decrypt it back, all locally in your browser. For learning, not real security.
Open ToolHash Type Identifier
Free hash identifier: paste a hash and get the likely algorithms based on its length and format — MD5, SHA family, bcrypt, and more — in your browser.
Open ToolLuhn Check Digit Calculator
Free Luhn calculator: validate a number against the Luhn algorithm and compute the check digit that makes it valid, entirely in your browser.
Open ToolKeyboard Shift Cipher
Free keyboard shift cipher moves characters along QWERTY rows by a chosen number of keys. Runs in your browser; no uploads or accounts are used.
Open ToolBcrypt Cost Estimator
Free bcrypt cost estimator that explains rounds, relative work, and expected scaling. Compare cost factors without hashing secrets.
Open ToolString Entropy Calculator
Free string entropy calculator: measure Shannon entropy and estimate password-style bits of strength for any text, computed locally in your browser.
Open ToolISBN Validator & Converter
Free ISBN tool: validate ISBN-10 and ISBN-13, and convert between them, with the check digit computed locally in your browser.
Open ToolAPI Key Generator
Free API key generator: create random keys and tokens in hex, alphanumeric, or URL-safe form using secure randomness, in your browser.
Open ToolBook Cipher
Free book cipher maps message words to first matching positions in a supplied reference passage. Runs in your browser; no uploads or accounts are used.
Open ToolChaocipher
Free Chaocipher encodes and decodes with two dynamically permuted twenty-six-letter alphabets. Runs in your browser; no uploads or accounts are used.
Open ToolKeyword Substitution Cipher
Free keyword substitution cipher builds a deduplicated keyed alphabet for reversible mapping. Runs in your browser; no uploads or accounts are used.
Open ToolPassword Generator
Generate strong random passwords locally with configurable length and character sets.
Open ToolPlayfair Cipher
Free Playfair cipher processes keyed letter pairs through a five-by-five square for both directions. Runs in your browser; no uploads or accounts are used.
Open ToolAtbash Cipher
Free Atbash cipher: reverse the alphabet so A becomes Z and B becomes Y. Encode and decode with the same step, all in your browser.
Open ToolRandom PIN Generator
Free random PIN generator: create secure numeric PINs of any length using your browser’s crypto random source.
Open ToolRunning Key Cipher
Free running key cipher adds or subtracts a nonrepeating passage at least as long as the message. Runs in your browser; no uploads or accounts are used.
Open ToolVigenere Cipher
Free vigenere cipher for cleaning, transforming, and checking pasted text. Process content locally in your browser without uploads.
Open ToolA1Z26 Cipher
Free A1Z26 cipher tool: convert letters to their alphabet numbers and back, computed locally in your browser.
Open ToolADFGX Cipher
Free ADFGX cipher combines a keyed Polybius fraction with keyword column transposition. Runs in your browser; no uploads or accounts are used.
Open ToolAffine Cipher
Free affine cipher tool: encode and decode text with the affine substitution formula, computed locally in your browser.
Open ToolAutokey Cipher
Free autokey cipher encodes and decodes letters with a keyword extended by the message. Runs in your browser; no uploads or accounts are used.
Open ToolFractionated Morse Cipher
Free fractionated Morse cipher groups keyed Morse streams into three-symbol substitutions. Runs in your browser; no uploads or accounts are used.
Open ToolHill Cipher 2x2
Free Hill cipher 2x2 multiplies letter pairs by an invertible matrix modulo twenty-six. Runs in your browser; no uploads or accounts are used.
Open ToolOne-Time Pad Cipher
Free one-time pad XOR cipher: encrypt text against a key to hex, and decrypt it back, computed locally in your browser.
Open ToolRagbaby Cipher
Free Ragbaby cipher shifts through a keyed alphabet by word number and letter position. Runs in your browser; no uploads or accounts are used.
Open ToolTap Code Translator
Free tap code translator converts letters to five-by-five row-column pairs and back again. Runs in your browser; no uploads or accounts are used.
Open ToolAlberti Cipher Disk
Free Alberti cipher disk rotates a movable alphabet by interval, offset, and step controls. Runs in your browser; no uploads or accounts are used.
Open ToolBase32 Encoder & Decoder
Free Base32 encoder and decoder using the RFC 4648 alphabet, computed locally in your browser.
Open ToolBase32 Encoder Decoder
Free Base32 encoder and decoder for RFC 4648 text values. Convert strings locally with padding support in your browser.
Open ToolBase58 Encoder Decoder
Free Base58 encoder and decoder using the Bitcoin alphabet. Convert text values locally without ambiguous characters.
Open ToolBifid Cipher
Free Bifid cipher fractionates keyed Polybius coordinates and recombines them by period. Runs in your browser; no uploads or accounts are used.
Open ToolCredit Card Payoff Calculator
Free credit card payoff calculator that estimates months and interest from balance, APR, and monthly payment. Runs locally in your browser for private planning.
Open ToolCredit Card Validator
Free credit card number validator: check a card number with the Luhn algorithm and detect the network, all locally with nothing stored or uploaded.
Open ToolMyszkowski Transposition Cipher
Free Myszkowski transposition cipher handles repeated keyword letters as shared rank groups. Runs in your browser; no uploads or accounts are used.
Open ToolPassword Strength Meter
Free password strength meter: estimate entropy in bits, rate strength, and get specific feedback — all locally in your browser with nothing stored.
Open ToolRail Fence Cipher
Free rail fence cipher: encode or decode text with a zigzag transposition across a chosen number of rails, entirely in your browser.
Open ToolStraddling Checkerboard Cipher
Free straddling checkerboard cipher assigns variable-length digit codes from two row markers. Runs in your browser; no uploads or accounts are used.
Open ToolAscii85 Encoder & Decoder
Free Ascii85 encoder and decoder: convert text to compact Ascii85 and back, computed locally in your browser.
Open ToolBacon Cipher
Free Baconian cipher tool: encode text into five-letter A/B groups and decode it back, computed locally in your browser.
Open ToolBase58 Encoder & Decoder
Free Base58 encoder and decoder using the Bitcoin alphabet, converting hex bytes, computed locally in your browser.
Open ToolBeaufort Cipher
Encode or decode text with the reciprocal Beaufort cipher and a repeating alphabetic key, preserving nonletters privately in your browser without uploads.
Open ToolCaesar Cipher
Free Caesar cipher tool: shift letters by any amount to encode or decode a message, computed locally in your browser.
Open ToolColumnar Transposition Cipher
Free columnar transposition cipher reorders text by alphabetically ranked keyword columns. Runs in your browser; no uploads or accounts are used.
Open ToolEAN & UPC Check Digit
Free EAN-13 and UPC check digit calculator: enter the digits to compute or verify the barcode checksum, computed locally in your browser.
Open ToolFour-Square Cipher
Free four-square cipher encodes digraphs with two keyed and two standard five-by-five squares. Runs in your browser; no uploads or accounts are used.
Open ToolGronsfeld Cipher
Free Gronsfeld cipher shifts letters with a repeating numeric key and reverses the shifts. Runs in your browser; no uploads or accounts are used.
Open ToolHomophonic Substitution Cipher
Free homophonic substitution cipher alternates two numeric symbols for each plaintext letter. Runs in your browser; no uploads or accounts are used.
Open ToolIBAN Validator
Free IBAN validator: check an international bank account number against the ISO mod-97 checksum and see its country and length, locally in your browser.
Open ToolNihilist Cipher
Free Nihilist cipher adds repeating keyed Polybius numbers and reverses the numeric sums. Runs in your browser; no uploads or accounts are used.
Open ToolPassphrase Generator
Free diceware-style passphrase generator: build memorable multi-word passphrases from a built-in list using secure randomness, all in your browser.
Open ToolPorta Cipher
Free Porta cipher applies reciprocal paired-alphabet substitutions with an alphabetic keyword. Runs in your browser; no uploads or accounts are used.
Open ToolROT13 Caesar Cipher
Free rot13 caesar cipher for cleaning, transforming, and checking pasted text. Process content locally in your browser without uploads.
Open ToolROT47 Converter
Free ROT47 converter: transform printable ASCII with the self-reversing ROT47 cipher, computed locally in your browser.
Open ToolRoute Transposition Cipher
Free route transposition cipher fills rows and reads a clockwise spiral through the grid. Runs in your browser; no uploads or accounts are used.
Open ToolTrifid Cipher
Free Trifid cipher fractionates characters through a keyed three-by-three-by-three cube. Runs in your browser; no uploads or accounts are used.
Open ToolPolybius Square Cipher
Free polybius square cipher for a focused result. It encodes letters as row-column digit pairs and decodes them with private local processing in your browser.
Open ToolScytale Cipher
Free scytale cipher writes text across a chosen number of rows and reads down columns. Runs in your browser; no uploads or accounts are used.
Open ToolTwo-Square Cipher
Free two-square cipher uses two keyed five-by-five alphabets and reciprocal rectangle pairs. Runs in your browser; no uploads or accounts are used.
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