Bitcoin Blockchain Set for September Split with BLAKE2b Fork

The Bitcoin blockchain is set to split on September 1, 2026, with a new chain launching that uses the BLAKE2b hashing algorithm instead of SHA-256d. This change will render all existing mining machines useless for the new chain, forcing miners to use ordinary processors or graphics cards.

According to the project's documentation, Bitcoin holders do not need to transfer or exchange their coins before the fork. Their addresses, keys, and coins will remain the same.

The BLAKE2b fork is being led by supporters of the Bitcoin Knots software, which offers stricter rules than Bitcoin Core. The driving force behind the project is developer Luke Dashjr, who wants to prise block production out of the hands of large mining operations.

One of the proposed starting difficulties for the new chain would require around 870 terahash per second, but the testnet4 environment under discussion was estimated at 50-70 terahash per second. This highlights the potential risk of a chain split, as the new chain may struggle to gain traction without sufficient hash power.