The CryptoSys API is a developer's toolkit of fast, efficient symmetrical cryptographic functions in Visual Basic, VBA, VB.NET/VB20xx, C/C++, C#, ASP, and Python. You can incorporate it in your own apps or call it from VBA applications like Access, Excel and Word. It provides four of the major block cipher algorithms, three stream cipher algorithms, including ChaCha20, key wrap, secure message digest hash algorithms including SHA-3, the HMAC, CMAC and KMAC message authentication algorithms, the Poly1305 one-time authenticator, a data compression facility, a password-based key derivation function (PBKDF2), the SCRYPT key derivation function, the ASCON cipher suite (Ascon-128 AEAD, Ascon-Hash and Ascon-Xof), a secure random number generator, and other cryptographic utilities. If you need to do "asymmetric" public key cryptography, look at our alternative product, the CryptoSys PKI Toolkit (see comparison API vs PKI).
Read the API Manual | Features | BUY NOW | Download Trial | Examples
2020-06-02: Released xmlsq our new free XML Simple Query utility. xmlsq is a simple lightweight utility to query XML documents using XPath 1.0. Use from the command line or via its programming interface.
“ This message is simply one of thanks for you developing this API. I have spent the last 2 days trying (in vain) to generate SHA256 and MD5 hashes in MS Access vba to support an interface to Amazon's REST MWS API. ”
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The block cipher algorithms in the CryptoSys API are:
The one-way message digest hash functions the Secure Hash Algorithm (SHA-1), SHA-224, SHA-256, SHA-384, SHA-512, SHA-3, MD5, MD2 and RIPEMD-160.
The random number generator complies with the Federal Information Processing Standards Publication FIPS PUB 140-2 Security Requirements for Cryptographic Modules. Data compression functions are included based on Jean-loup Gailly's excellent 'zlib' product. One technique of compression and encryption is shown in our demonstration VB6 project of MySecret with CryptoSys API.
Random Number Generator (RNG): Version 4 of CryptoSys API includes an improved thread-safe random number generator (RNG) based on the strict NIST SP 800-90 standard†. This is compliant with FIPS PUB 140-2. To that end, we publish the full details of the random number algorithms used in CryptoSys. Your comments and review are welcome.
† Note 2013-09-21: Our implementation does not use the Dual EC_DRBG component of NIST 800-90 that is alleged to contain an NSA backdoor.
The CryptoSys API functions allow you to encrypt, decrypt, hash and authenticate data in a variety of formats, as well as generating secure random keys to use in your applications. Your input data can generally be in a byte array, encoded as a hexadecimal string, or in a file. The functions can process the data in a one-off manner, or, for longer inputs, you can call the "update" functions sequentially after initialising. The block cipher algorithms work in Electronic Codebook (ECB), Cipher Block Chaining (CBC), Cipher Feedback (CFB), Output Feedback (OFB) and Counter (CTR) modes. AES with Galois/Counter Mode (AES-GCM) is provided. You can generate random keys and nonces in a secure manner. All functions are thread-safe. See the Examples page.
For a quick guide on how to create a C# project see Creating a C# command-line app with CryptoSys API.
The CryptoSys API uses a straightforward and independent Win32 DLL which is compatible with all modern versions of Windows XP and above (W10/W8/W7/2008/Vista/2003/XP). A 64-bit DLL is also provided. There is no "COM", no "Active-X", and no requirement to "register" it with Windows to use it. The products do not use or rely on the Microsoft Cryptographic API (CRAPi [sic]) cryptographic providers in any way. Developers can distribute to their clients by simply copying a single file into the correct directory. For those users who do want ActiveX capability so they can call it from an ASP page, there is a free (unsupported) ActiveX Interface (32-bit platforms only).
There is a test bed demo program
CryptoSys5A.exe distributed with
CryptoSys API. Use this to experiment with different combinations of encryption algorithms, block cipher modes, padding, hex and alpha input, and more.
See CryptoSys API Testbed Demo Help for more information.
Download the latest Trial Edition of CryptoSys API now.
Most recent production version 6.22.1 compiled 7 January 2024. Use either
Unzip the zip file and run the
install.exe program inside it, or download the exe program directly and run it.
The Trial Edition is fully-functional and the download includes a set of test functions in Visual Basic (VB6/VBA), VB.NET, C, C++ (STL) and C#. Please read the licence conditions for the Trial Edition. The trial period is 60 days from the date first installed on your system. For programming references see the documentation page.
You need to have administrator rights when installing and uninstalling.
Install for Server when installing just means it disables pop-up messages
if you try and run it without installing correctly or if it's expired.
Leave the option unchecked for a desktop.)
You can purchase a licenced version here. Existing licence holders can download the latest Developer Edition here.
See Writing an interface in another programming language for advice and examples in how to use CryptoSys API with other programming languages, including Visual FoxPro and Team Developer.
For Delphi, see the page Using Delphi with CryptoSys API, CryptoSys PKI and FirmaSAT for more details and some sample code.
See Using CryptoSys API with Microsoft Excel for an example of how to call a function in CryptoSys API from an Excel spreadsheet.
As of version 6.20, all the necessary 32- and 64-bit declarations are included in the one module
The old ~64.bas and ~64_32.bas files are now redundant.
VB6 programmers (yes, we know you are still out there) should check
Why are some lines showing in red in my IDE?.
Check the integrity of your CryptoSys API software.
Please refer to our brief introductions to Using Keys in Cryptography and Using Padding in Encryption.
No. For public key cryptography, see our CryptoSys PKI Toolkit.
For more information, please send us a message.
This page last updated 7 January 2024