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.

PKI hierarchies - 1, 2, 3 tiers ?
Implementing Cryptography
Signing
Tech Update
Ejbca
Signserver
26 August, 2025

#KEYMASTER: Stateless PQC Digital Signatures: Insights into ML-DSA & SLH-DSA

In this #KEYMASTER episode, David Hook, VP of Software Engineering for Bouncy...
Keyfactor Release
Java FIPS
Release
22 August, 2025

Update about Release – Bouncy Castle Java FIPS 2.1.1

We would also like to inform you that official CVEs have now been issued for...
Keyfactor Release
Java FIPS
Release
22 August, 2025

New Release: Bouncy Castle Java FIPS 2.0.1

Bouncy Castle Java FIPS 2.0.1 We are pleased to announce the availability of...

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