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Will quantum computers get to our bitcoins? We examine the real threat
Hello everyone! I recently came across Google's latest Quantum AI report for 2026, and frankly, the numbers are quite thought-provoking. Until recently, we dismissed quantum computers as mere fairy tales of the distant future. But now it's clear—the threat is closer than we thought. Let's break down how these supermachines are breaking crypto, why Ethereum turned out to be more vulnerable than Bitcoin, and what we can do about all this to avoid one day seeing our balance fall to zero.
How Security Works: A Meat Grinder Example
Bitcoin's security is based on mathematics, which can be best compared to a regular meat grinder. Your private key (roughly speaking, your password to your money) is a piece of meat. Your public key (from which your address is generated) is the ground meat. Grinding the meat and getting the ground meat is easy. But reassembling the original piece of meat from the ground meat is mathematically impossible.
This trick is called the discrete logarithm problem, and the entire network rests on it. It would take a conventional supercomputer hundreds of billions of years to find the combinations, because there are almost as many possible addresses in Bitcoin as there are atoms in the universe.
So what's the problem?
A quantum computer works fundamentally differently. It doesn't brute-force. Using what's called Shor's algorithm, it calculates the required key directly.
Previously, everyone slept soundly because they thought such a hack would require tens of millions of qubits (computing elements). But in March 2026, Google published a report on new error correction algorithms (Quantum LDPC). The result is that hardware requirements have plummeted tenfold. Now, hacking requires less than 500,000 physical qubits.
But that's not the most challenging aspect. The report calculated that cracking the key would take about 9 minutes. And a Bitcoin block takes an average of 10 minutes to mine. So, when you submit a transaction to the mempool, a quantum computer has exactly 9 minutes to calculate your key and intercept the coins on the fly.
Why Satoshi is a genius, and Ethereum is in danger
. Here's the key. Shor's algorithm is completely blind until it sees your public key in its raw form.
In Ethereum, the system works like a regular bank account—you reveal your public key with the first transaction, and it remains publicly accessible forever.
Bitcoin, however, uses a UTXO model. It's like one-time-use sealed bottles of coins. The key is that your wallet address isn't the public key itself, but only its hash (an encrypted fingerprint). Until you send money to someone, the public key is hidden, and a quantum computer has nothing to latch onto. It sees a locked safe without a keyhole. The threat arises the moment you press "Send," and your key is forever imprinted on the blockchain. Satoshi Nakamoto did this for anonymity, but in reality, he accidentally created the perfect quantum shield.
Whose bitcoins are at risk?
According to Ark Invest, approximately 7 million bitcoins (33% of all coins) are currently held in addresses with public keys.
Who specifically is at risk?
When will it hit? (Q-Day)
In cryptography, there's a term called Q-Day – the day when a quantum computer will be able to break modern ciphers. Scientists are no longer debating whether this will happen, but when exactly. Google plans to build such a machine by 2029. And the US government and the Pentagon have ordered their agencies to transition to post-quantum standards no later than 2035. So, we have 3 to 9 years to spare. It seems like plenty of time, but for crypto, that's literally tomorrow.
What to do right now:
There's no need to panic and dump your crypto. Developers are already actively testing updates (for example, BIP 360, which completely hides the public key from transactions). But basic security needs to be ensured today.
1. Check your addresses. Go to quantumrect.com – it's an offline checker from cypherpunks, it's completely secure. Enter your address. If the status is green, your key is hidden, everything is fine. If it displays a red "rect" sign, it means the key is already exposed on the blockchain.
2. Transfer funds. If your primary address is exposed, simply create a new wallet and transfer your bitcoins there. The main rule is to not send anything else from the new address. Until the key is online, the algorithms are powerless.
Hello everyone! I recently came across Google's latest Quantum AI report for 2026, and frankly, the numbers are quite thought-provoking. Until recently, we dismissed quantum computers as mere fairy tales of the distant future. But now it's clear—the threat is closer than we thought. Let's break down how these supermachines are breaking crypto, why Ethereum turned out to be more vulnerable than Bitcoin, and what we can do about all this to avoid one day seeing our balance fall to zero.
How Security Works: A Meat Grinder Example
Bitcoin's security is based on mathematics, which can be best compared to a regular meat grinder. Your private key (roughly speaking, your password to your money) is a piece of meat. Your public key (from which your address is generated) is the ground meat. Grinding the meat and getting the ground meat is easy. But reassembling the original piece of meat from the ground meat is mathematically impossible.
This trick is called the discrete logarithm problem, and the entire network rests on it. It would take a conventional supercomputer hundreds of billions of years to find the combinations, because there are almost as many possible addresses in Bitcoin as there are atoms in the universe.
So what's the problem?
A quantum computer works fundamentally differently. It doesn't brute-force. Using what's called Shor's algorithm, it calculates the required key directly.
Previously, everyone slept soundly because they thought such a hack would require tens of millions of qubits (computing elements). But in March 2026, Google published a report on new error correction algorithms (Quantum LDPC). The result is that hardware requirements have plummeted tenfold. Now, hacking requires less than 500,000 physical qubits.
But that's not the most challenging aspect. The report calculated that cracking the key would take about 9 minutes. And a Bitcoin block takes an average of 10 minutes to mine. So, when you submit a transaction to the mempool, a quantum computer has exactly 9 minutes to calculate your key and intercept the coins on the fly.
Why Satoshi is a genius, and Ethereum is in danger
. Here's the key. Shor's algorithm is completely blind until it sees your public key in its raw form.
In Ethereum, the system works like a regular bank account—you reveal your public key with the first transaction, and it remains publicly accessible forever.
Bitcoin, however, uses a UTXO model. It's like one-time-use sealed bottles of coins. The key is that your wallet address isn't the public key itself, but only its hash (an encrypted fingerprint). Until you send money to someone, the public key is hidden, and a quantum computer has nothing to latch onto. It sees a locked safe without a keyhole. The threat arises the moment you press "Send," and your key is forever imprinted on the blockchain. Satoshi Nakamoto did this for anonymity, but in reality, he accidentally created the perfect quantum shield.
Whose bitcoins are at risk?
According to Ark Invest, approximately 7 million bitcoins (33% of all coins) are currently held in addresses with public keys.
Who specifically is at risk?
- Ancient addresses from Satoshi's time (Pay to Public Key) and newer Taproot addresses (starting with BC1P) reveal the key from the start. Legacy addresses (starting with 1), Segwit (BC1Q), and Pay to Script Hash (starting with 3) are completely secure until you spend at least some of the funds from them. Once you make an outgoing transfer, your key is exposed.
When will it hit? (Q-Day)
In cryptography, there's a term called Q-Day – the day when a quantum computer will be able to break modern ciphers. Scientists are no longer debating whether this will happen, but when exactly. Google plans to build such a machine by 2029. And the US government and the Pentagon have ordered their agencies to transition to post-quantum standards no later than 2035. So, we have 3 to 9 years to spare. It seems like plenty of time, but for crypto, that's literally tomorrow.
What to do right now:
There's no need to panic and dump your crypto. Developers are already actively testing updates (for example, BIP 360, which completely hides the public key from transactions). But basic security needs to be ensured today.
1. Check your addresses. Go to quantumrect.com – it's an offline checker from cypherpunks, it's completely secure. Enter your address. If the status is green, your key is hidden, everything is fine. If it displays a red "rect" sign, it means the key is already exposed on the blockchain.
2. Transfer funds. If your primary address is exposed, simply create a new wallet and transfer your bitcoins there. The main rule is to not send anything else from the new address. Until the key is online, the algorithms are powerless.