Provably Unspendable Bitcoin
An overview of provably unspendable bitcoin — coins that will never move again.
Unlike lost private keys (which are probably gone but technically still spendable), provably unspendable bitcoin can be verified by anyone from the blockchain alone.
The figure is derived from the difference between Bitcoin's gross issued supply and the actual UTXO set total reported by gettxoutsetinfo.
It reflects three distinct categories: a hardcoded quirk in the genesis block, miners who failed to claim their full subsidy, and outputs deliberately rendered unspendable via OP_RETURN.
The total is shown live on the Supply page as Unspendable. This page breaks down where those coins came from.
| Category | Amount | % of Total | Details |
|---|---|---|---|
|
Genesis Block Coinbase
|
50.00000000 ₿ | – |
Block 0 — mined by Satoshi Nakamoto on 3 January 2009. The 50 BTC coinbase reward is hardcoded as unspendable in Bitcoin Core due to a quirk in the original implementation: the genesis block's coinbase transaction is not included in the UTXO set. This was likely an oversight rather than a deliberate decision. Every Bitcoin node enforces this since block 0.
|
|
Unclaimed Block Subsidies
|
18.75000001 ₿ | – |
3 blocks where the miner's coinbase transaction claimed less than the protocol-defined subsidy. These coins were never issued — they never entered circulation.
View full list →
|
|
OP_RETURN Burns
|
~161.34 ₿ | – |
Outputs with
OP_RETURN (script type nulldata) carrying a non-zero value. Bitcoin Core never adds these to the UTXO set — they are unspendable by design. Used for proof-of-burn, protocol bootstrapping, and data embedding.
|
Total |
– | 100% |
Bitcoin Core's gettxoutsetinfo returns the total value of all spendable UTXOs at a given height.
Comparing this to the gross issued supply (the sum of all coinbase subsidies actually paid out up to that height) gives the total provably unspendable amount.
Gross issued ≠ theoretical maximum. The theoretical maximum supply of 20,999,999.9769 ₿ is the sum of all protocol-defined subsidies across every future halving epoch until the last satoshi is mined around the year 2140. The gross issued supply at the current block height is lower — it only counts subsidies already paid. The unclaimed subsidies reduce the theoretical maximum, giving an effective hard cap of –.
This figure does not include coins sent to addresses with no known private key (e.g. 1CounterpartyXXXXXXXXXXXXXXXUWLpVr) — those outputs are still technically spendable and remain in the UTXO set.
Provably unspendable means the script itself makes spending impossible, regardless of who holds what key.