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PrismKit

Caesar Cipher

Local

Shift letters with a Caesar, ROT13 or ROT47 cipher, or crack one by ranking all 25 shifts against English letter frequencies.

VAT Number Validator

Check the format and check digits of EU and UK VAT numbers offline.

Vigenère Cipher

Encrypt or decrypt with the Vigenère, Beaufort or autokey cipher and guess an unknown key with Kasiski and index-of-coincidence analysis.