KoinlyticsBRC-20 was the first practical way to issue fungible tokens on Bitcoin. Created by an anonymous developer named domo in March 2023 shortly after Ordinals shipped, it used inscriptions to declare token operations. At peak in mid-2023 it drove much of Bitcoin's fee revenue and created markets worth billions.
Mechanics
Every action is a JSON inscription:
- Deploy. Inscribe {"p":"brc-20","op":"deploy","tick":"ORDI","max":"21000000","lim":"1000"}.
- Mint. Inscribe {"p":"brc-20","op":"mint","tick":"ORDI","amt":"1000"}.
- Transfer. Inscribe a transfer intent, then send the inscription to the recipient.
Off-chain indexers watch for these inscriptions and maintain balances. There is no consensus on which indexer is correct.
Indexer problem
Different indexers can disagree on edge cases (double-inscribed transfers, replaced-by-fee ambiguities). Wallets have to pick which indexer to trust. This is BRC-20's biggest weakness and the direct reason Runes was designed.
The 2023 mania
ORDI (first BRC-20 token deployed) reached a $1B+ market cap. Multiple BRC-20 tokens spun up including SATS, RATS, TRAC. Wallets like UniSat and OKX Wallet raced to add support.
Where BRC-20 stands now
Volume declined after Runes launched. Some legacy BRC-20 tokens still trade. New Bitcoin fungibles increasingly use Runes or Taproot Assets. BRC-20's legacy is proving Bitcoin could host fungible markets at all.