Crypto or Krypto may refer to:

• Cryptography, the practice and study of hiding information
• Cryptanalysis, the study of methods for obtaining the meaning of encrypted information
• CRYPTO (conference), an annual cryptographical and cryptoanalytic conference
• Crypto++, a free, open source library of cryptographic algorithms and schemes
• , a book about cryptography by Steven Levy
• Crypto AG, a Swiss manufacturer of encrypted communications products
• Cryptocurrency, digital currency that uses cryptography to secure transactions

Crypto++ (also known as CryptoPP, libcrypto++, and libcryptopp) is a free and open source C++ class library of cryptographic algorithms and schemes written by Wei Dai. Crypto++ has been widely used in academia, student projects, open source and non-commercial projects, as well as businesses. Released in 1995, the library fully supports 32-bit and 64-bit architectures for many major operating systems and platforms, including Android (using STLport), Apple (Mac OS X and iOS), BSD, Cygwin, IBM AIX and S/390, Linux, MinGW, Solaris, Windows, Windows Phone and Windows RT. The project also supports compilation under C++03 and C++11, a variety of compilers and IDEs, including Borland Turbo C++, Borland C++ Builder, Clang, CodeWarrior Pro, GCC (including Apple's GCC), Intel C++ Compiler (ICC), Microsoft Visual C/C++, and Sun Studio.

CRYPTO, the International Cryptology Conference, is one of the largest academic conferences in cryptography and cryptanalysis. It is organized by the International Association for Cryptologic Research (IACR), and it is held yearly in August in Santa Barbara, California at the University of California, Santa Barbara.