Google has given the tech sector a clear date. By 2029, the company wants all of its systems protected against quantum computers. That matters far beyond Google. Bitcoin relies on the same broad family of cryptographic tools, so the pressure is growing on developers, wallet providers, and coin holders to think ahead.
Important to Know
- Google says quantum computers are a real threat to current encryption and digital signatures.
- Around 6.5 million BTC is considered vulnerable, although much of it may already be lost forever.
- Bitcoin itself is not broken at the blockchain level, but some wallet addresses could become exposed.
A lot of the risk comes down to keys. Every Bitcoin wallet uses a public key and a private key. You can think of the public key like an account number, while the private key acts more like the secret proof that lets you spend the coins. Right now, ordinary computers cannot realistically work backward from the public key to the private key. In theory, though, a powerful enough quantum computer could do that with a special algorithm.
So the real danger is not that the Bitcoin network suddenly stops working. The blockchain, meaning the chain of blocks that records transactions, would keep running. The hash functions that link those blocks together are still considered resistant to quantum attacks. Instead, the bigger concern is with certain addresses and old coins.
That is why JP Richardson, CEO of software company Exodus, reacted so sharply on X. He said: “This means that Bitcoin has three years to migrate more than 6.5 million BTC in vulnerable addresses. This is the hardest coordination challenge in Bitcoin history.”
The number comes from a report by the Human Rights Foundation. According to that report, about 6.5 million Bitcoin could be at risk. Of that total, 1.72 million BTC sits in old addresses that are likely lost or cannot be moved, including the estimated 1.1 million coins linked to Satoshi Nakamoto. Another 4.49 million BTC is held in reused addresses, where owners may still be able to move funds to safer setups.
Older wallets face the biggest questions. In the earliest Bitcoin addresses, including those connected to Satoshi, the public key is directly visible on the blockchain. The same can happen when someone sends Bitcoin and later receives more on the same reused address. Once the public key is exposed, quantum risk becomes a more direct concern.
Google added fuel to the debate by saying progress in quantum hardware and error correction is moving fast enough to make action more urgent. The company said: “Quantum computers pose a significant threat to current cryptographic standards, specifically to encryption and digital signatures.” Google is also building toward that future itself through Willow, a 105 qubit quantum processor. Willow is nowhere near strong enough to break modern security today, but the pace of development is what has people paying attention.
Get Moving Already?
The Bitcoin community is still split on how serious the problem really is and how quickly anything should happen. Adam Back, the head of Blockstream and a British cryptographer with an important place in the technical roots of Bitcoin, has argued that the fears are badly overstated and that no action will be needed for decades.
Others are taking a more urgent line. Security researcher Ethan Heilman has proposed BIP 360, a plan meant to protect Bitcoin addresses from quantum attacks. Even then, the process would be slow. According to the discussion around the proposal, rollout could still take about seven years.
One point is worth keeping in mind. A BIP is a Bitcoin Improvement Proposal. In simple terms, it is a formal way to suggest changes to Bitcoin. Even strong proposals take time because Bitcoin is decentralized, which means no single company or person can force everyone to upgrade at once.
ARK Invest and Unchained offered a more measured view in a joint report. They do not expect a sudden Q Day, the term used for the moment a quantum computer becomes powerful enough to crack current protections. Instead, they expect a gradual build, which would give the market time to react and adapt.
So we are looking at a race between two things: quantum progress and crypto coordination. Google has now pinned its own deadline to 2029. Ethereum is laying groundwork. Solana has added an early tool. Bitcoin is still debating whether the threat is close, distant, or somewhere in between. Meanwhile, millions of coins remain tied to address types that could become a problem if the technology arrives faster than expected.