BRC-20

BRC-20 uses Ordinals inscriptions to store JSON objects with three operations: deploy (defining the token with its tick, max supply and per-mint limit), mint and transfer. It has no smart contracts or real on-chain logic, so the truth of each balance is computed by off-chain indexers that read and interpret the inscriptions in order. It is a metaprotocol of social convention, not a consensus rule, and by design it generates many inscriptions and transactions.

It proved fungible tokens could be issued on Bitcoin without changing the protocol, which set off the 2023 Ordinals and inscriptions cycle and motivated cleaner alternatives such as Runes. For a product team it is a useful case study on the difference between a formal standard that went through the BIP process and a convention living entirely outside consensus, with the dependence on external indexers that this entails.

BRC-20 was created and deployed on 8 March 2023 by a pseudonymous programmer known as Domo, and its name is an intentional echo of Ethereum's ERC-20, read as Bitcoin Request for Comment 20. The first deployed token was ORDI. Domo himself explicitly warned that the standard is fun and experimental, and that it should not be considered the standard for fungibility on Bitcoin.