- Public-key exposure in taproot addresses may enable quantum computing to derive private keys.
- Users are advised to store coins in SegWit BC1Q addresses and avoid spending until the upgrade.
Concerns are growing over the impact of quantum computing on Bitcoin’s long-term security. Analysts are warning that these machines, expected to reach advanced capability within the next decade, could potentially undermine the cryptographic foundations that secure trillions in BTC holdings.
On-chain analyst Willy Woo cautioned that the next stage of computing power may expose Bitcoin users to risks previously unconsidered. He said the era of “big scary quantum computers ” could render traditional key protection methods ineffective, as they may be able to derive private keys directly from public keys.
Woo explained,
In the past it was about protecting your PRIVATE KEY (your seed phrase). In the age of big scary quantum computers (BSQC) that are coming, you need to protect your PUBLIC KEY also.
DUMMIES GUIDE TO BEING QUANTUM SAFE.
In the past it was about protecting your PRIVATE KEY (your seed phrase). In the age of big scary quantum computers (BSQC) that are coming, you need to protect your PUBLIC KEY also.
Basically a BSQC can figure out your private key from a…
— Willy Woo (@woonomic) November 11, 2025
Secure Coins with Segwit Approach
Analyst Woo said that current taproot addresses, which begin with “bc1p,” embed the public key into the address format. He warned that this makes them unsafe under potential quantum attacks.
Older address types that start with “1,” “3,” or “bc1q” conceal the public key behind a hash, making them harder to crack. He suggested Bitcoin users shift their funds to older address formats until the network upgrades to a quantum-resistant protocol. Woo said,
Create a new segwit wallet. It will start with ‘bc1q’ (NOT ‘bc1p’)… send all your BTC into this new address… NEVER send BTC out of it, once you do you’re BSQC hackable because your public key is revealed.
He also mentioned that any future transfer into a quantum-safe address should be done when the network is not heavily loaded. During a transaction, there is a short period where the key is exposed, though he believes the practical risk during that brief window is low. He added,
Send your BTC into the new quantum safe address when the network is NOT congested, once you send, you reveal the private key for a short time. It’s unlikely a BSQC will steal your coins in that short window.
Woo estimated that Bitcoin could take up to seven years to develop and implement a reliable quantum-safe protocol.
Dormant Early Bitcoin Now At Risk
Large holders such as ETFs, corporate treasuries, and exchanges can still safeguard their reserves before the network transitions to new encryption standards. Woo stated that custodians can act now to prevent exposure, suggesting that
Wallet Apps can also take appropriate action (making sure any spend from an address also moves remaining coins to a new non-taproot address).
However, dormant Bitcoin from the early years faces a dire outlook. Woo added that Satoshi Nakamoto’s estimated 1 million BTC, locked in early P2PK addresses, could eventually be taken unless future protocol updates freeze those coins. Lost coins with prior transaction histories may also be vulnerable once quantum computers advance.
Kostas Kryptos Chalkias, co-founder and chief cryptographer of Mysten Labs, offered a more conservative timeline for the risk. “There’s no evidence today that any computer, even a classified one, can break modern cryptography,” he said. “We’re at least 10 years away from that.”
The period after 2030, referred to by some experts as “Q-Day,” is considered the likely window when quantum systems could begin posing real threats to cryptographic networks like Bitcoin. Until then, analysts believe proactive steps could minimize exposure.
At present, Bitcoin is trading around $105,075, down 1.54% over the last 24 hours.