35.4% of Bitcoin Supply Shows Public Keys On-Chain

Bitcoin public keys are visible on-chain for 35.4% of the total supply, an on-chain classification shows, placing roughly 7.12 million BTC in a group that a future quantum computer could theoretically target. The measurement describes exposure, not loss. No coins in this group have been taken, and the source data contains no report of theft.

The figure comes from an on-chain measure that classifies the Bitcoin supply according to whether the public key behind each holding is visible on the blockchain. Under Bitcoin's elliptic-curve cryptography, a public key must be revealed before coins can be spent. Once revealed, the key sits permanently in the transaction record. The classification therefore separates holdings whose keys are already exposed from holdings still protected behind hashed addresses.

What does the 35.4% figure actually mean?

The number quantifies potential exposure, and nothing more. It is not a count of stolen coins. The threat model requires a quantum computer capable of breaking the cryptography securing those visible keys. No such machine is known to exist today. The exposure is conditional on a future technical capability that has not arrived, and the source presents it strictly in those terms.

That conditional framing matters. A headline figure of 7.12 million BTC invites the reading that nearly two-fifths of Bitcoin's supply is immediately at risk. The on-chain data supports no such claim. What it supports is narrower: about 7.12 million BTC, roughly 35.4% of supply, sit in addresses where the public key is already visible rather than hidden behind an address hash.

How can holders remove the exposure?

The remedy, according to the source, is operational rather than technological. A transfer of affected holdings to fresh addresses removes the public-key visibility risk. New addresses keep the public key concealed until the holder spends. In plain terms, an owner who moves exposed coins to a clean address exits the at-risk classification without waiting for the cryptography itself to change.

This creates an uneven remediation picture. Sophisticated custodians and active holders can rotate holdings on their own schedule. Dormant coins, including holdings in addresses whose owners may be unreachable or inactive, present a harder problem. The source data does not break down the 7.12 million BTC by wallet activity, age or ownership type, so the share that can realistically be rotated remains unknown.

What is not said in the data?

The classification stops at visibility. It does not estimate the cost of a quantum attack, the timeline for quantum hardware capable of such an attack, or the share of exposed coins held by long-dormant addresses. Each of those gaps bears directly on how urgent the exposure is, and none is filled by the source. Any assessment of practical risk requires information beyond this measurement.

The takeaway is plain: about a third of Bitcoin's supply has revealed its public keys, holders can close that exposure by rotating to fresh addresses, and whether they do so at scale will determine how much of the 7.12 million BTC remains in the visible-key class as quantum computing advances.