Bouncy Castle – Open-source cryptographic APIs
Welcome to the home of the Legion of the Bouncy Castle and its FIPS-certified open-source cryptographic APIs for Java and C#.

Download Bouncy Castle
Download the Bouncy Castle APIs for Java, Java FIPS, Java LTS, C# .NET, C# .NET FIPS or the Kotlin version.
Read the Documentation
Access necessary resources for your project here: installation instructions, configuration guides, test examples, and much more.
Join the Discussion
You can ask your questions and learn from specialists in the Bouncy Castle forum on GitHub Discussions.
Here at the Legion of the Bouncy Castle, we believe in cryptography
We have been providing cryptography solutions for over 20 years, offering FIPS certifications, LTS releases, and quantum-ready support to meet everyone's needs.
Years of history
Years FIPS certified
Downloads per month
Get inspired
Stay up-to-date on the latest Bouncy Castle news and updates through our news feed. From product releases to the newest tutorial videos, guides, and events, our feed provides the latest information on all things related to Bouncy Castle.
#KEYMASTER: Understanding VEX and the Future of Vulnerability Management
#KEYMASTER: The Rise of SBOMs – A Growing Necessity
PQC and Lightweight Cryptography Updates – Bouncy Castle 1.80 Java
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