01 / Explainer
What is BTCB2?
BTCB2 is a community-led experiment: a Bitcoin hard fork with a new proof-of-work algorithm. The goal is not to replace Bitcoin, but to explore a different path while preserving the parts of the model that made Bitcoin useful.
BIP-110 origin
BTCB2 traces its proposal lineage to BIP-110, a community discussion around changing Bitcoin’s mining algorithm. The fork turns that idea into an independently run network.
Why BLAKE2b
BLAKE2b was selected for its modern design, fast software implementations, and well-studied cryptographic properties. It also creates a clean separation from SHA-256d mining.
A separate network
A hard fork is not an upgrade to mainnet. BTCB2 has its own chain state, nodes, miners, and ecosystem. Assets and assumptions must not be mixed between networks.
The key difference
Same roots. Different work.
Bitcoin mainnet uses SHA-256d, applying SHA-256 twice in its proof-of-work process. BTCB2 uses BLAKE2b instead. That single consensus change has practical consequences for miners, hardware, network security, and the economics around block production.
Other protocol details may evolve as the project matures. Always compare the exact release notes and source code rather than relying on summaries or social posts.