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#.

Legion of the Bouncy Castle

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.

25

Years of history

8

Years FIPS certified

6.2M

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.

Keyfactor Tech Update image
Implementing Cryptography
Installation & Deployment
News
6 August, 2025

Bouncy Castle Joins the CVE Program as a Numbering Authority (CNA)

We are proud to share that This milestone marks a key step forward in our co...
Keyfactor Release image
C#
Release
5 August, 2025

C# .NET Release 2.6.2 is now available for download

Bouncy Castle C# .NET Release 2.6.2
Keyfactor Release image
C# .NET FIPS
Java FIPS
News
Release
1 August, 2025

Patch Releases Now Permitted for FIPS-Certified Bouncy Castle Java and C# .NET

With the recent approval of the , we are aligning our support of FIPS-certifi...

Related open-source projects