# counter

URL: https://blockspace.wiki/glossary/counter/

A Bitcoin Counter is "a numbered file event": a file committed to Bitcoin as the description of a [Counterparty](https://blockspace.wiki/glossary/counterparty/) asset, carried in a [Counterparty taproot envelope](https://blockspace.wiki/glossary/taproot-envelope/), and given a global, gap-free number in order of creation, from #0. It passes two tests at once: the bytes are the description of a valid Counterparty issuance or [fairminter](https://blockspace.wiki/glossary/fairminter/) deploy, and they reached the chain inside [witness data](https://blockspace.wiki/glossary/witness/). Either test alone is nothing.

Counter #0 is XDUALS, at block 902,005, five blocks after Counterparty's taproot activation at block 902,000. The protocol adds nothing on chain: it is a numbering lens over events Counterparty already parses.

Sources:

- Bitcoin Counters build reference v3 · https://github.com/BitcoinCounters/counters/blob/HEAD/docs/build-reference-v3.md
- Bitcoin Counters v3, indexer and wallet: README (BitcoinCounters/counters) · https://github.com/BitcoinCounters/counters

Updated: 2026-10-20