Supply & Issuance

Provably Unspendable Bitcoin

An exact, block-aligned reconciliation of scheduled supply that is permanently absent from the UTXO set.

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 total below is scheduled supply minus Bitcoin Core's UTXO set amount at the same block hash. It reconciles exactly to Core's four categories: genesis, BIP30 overwrites, unclaimed block rewards, and provably prunable outputs. Unclaimed rewards are shown below as separate subsidy and fee amounts.

The same total is shown on the Supply page as Permanently Excluded. It does not include script-locked outputs that Bitcoin Core still retains in the UTXO set; known examples are shown separately below.

Never entered the UTXO set is a strict subset of Permanently Excluded, not a competing total.

– on Output Types = – provably prunable outputs + – Genesis.

The remainder of Permanently Excluded is – BIP30, represented in output lifecycle as two Removed without spend outputs, plus – unclaimed rewards, for which no output was ever created.

Provably prunable scriptPubKey bytes are measured directly from every matching output. Genesis, BIP30, and unclaimed reward losses are monetary effects rather than separate payloads, so they have no distinct byte count here.

Bitcoin Core's gettxoutsetinfo returns the total value retained in the UTXO set. We subtract that amount from the protocol's scheduled supply at the same height, then independently sum genesis, BIP30, unclaimed rewards, and provably prunable outputs. The result is published only when both sides agree exactly at the satoshi level and all sources share one block hash.

Scheduled supply to date ≠ 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 2139. Scheduled supply to date is the height-derived portion of that schedule. Known unclaimed subsidies reduce the maximum amount that can ever be issued, but they do not change Bitcoin's consensus subsidy limit.

This total does not include coins sent to addresses with no known private key, nor scripts that remain in the UTXO set even when separate script analysis can prove they are unsatisfiable.

A separately verified – remains inside Money Supply (UTXO Set Amount), but cannot be spent.

When mining pool software contains a bug that produces malformed coinbase output scripts, the coins can become permanently locked. A typical example is a script intended to be a standard P2WPKH output (OP_0 <20‑byte‑hash>, 22 bytes) that gets padded with extra zero bytes. In Bitcoin Script, each 0x00 byte is interpreted as OP_0, which pushes a falsy (empty) value onto the stack. If the script ends with OP_0, the top of the stack is always false after execution - regardless of what scriptSig a spender provides. No valid spending transaction can ever satisfy such a script. The coins are locked permanently.

Bitcoin Core classifies these outputs as "type": "nonstandard". Unlike provably prunable outputs, these scripts are added to the UTXO set - so gettxoutsetinfo includes their value. That is why they do not appear in Permanently Excluded above. They are nevertheless provably unspendable by script analysis alone.