BTC Beacon
connecting…

Live on BSV mainnet · since block 957,447

The Bitcoin light client
nobody can switch off.

BTC Beacon is a live Bitcoin light client that exists as a single self-sustaining artifact on the BSV blockchain. It verifies real Bitcoin block headers — proof-of-work, difficulty retargets, timestamp rules — and anyone on Earth can advance it by submitting the next headers for a fraction of a cent. Nobody can stop, pause, or own it.

Beacon has verified up to Bitcoin block height, checked header by header
Bitcoin network is at the live chain tip the beacon is walking toward

verified tip hash the leading zeros are the work — the beacon checked every one

Proof it’s alive

Every advance is a public transaction on the BSV chain. This is the beacon’s lineage — newest first, each entry a permanent record anyone can look up.

  1. Loading lineage…

The weight of the chain

Every Bitcoin header carries proof-of-work. The beacon checks it, adds it up, and carries the total forward. Rewriting what the beacon has verified would mean redoing all of it.

double-SHA256 computations verified

Anyone can advance it

Advancing the beacon means handing it the next Bitcoin headers and a few hundred satoshis for its trouble. The beacon checks the work itself — if the headers are real, it moves; if they’re not, it refuses.

Request a crank Ask the beacon to fetch and verify the next headers now.

Public cranking opens soon. On this demonstration instance the beacon advances on a schedule.

Checkpoints

A checkpoint is a fixed, citable record: the beacon’s verified Bitcoin tip — height, hash, and accumulated work — frozen at a moment in time, under a transaction id anyone can look up forever. A contract, an auditor, or another service can point at a checkpoint instead of trusting someone’s word for what Bitcoin said.