Could quantum computers ever breaks bitcoin security

[HMb1996]

U have been reading  about quantum computing and i have occasionally come
Across claims that it could one day breaks the crypto graphic algorithm used by
Bitcoin. As a beginner, i want to understand what that will means In practice
   If the quantum computers becomes capable of breaking bitcoins security
Would bitcoin holders have enough time to move their coin to quantum resistance addresses
 Could bitcoins network be upgraded to defend against such threaten
Would older wallet be more vulnerable than the new ones
I would be glad if crypto enthusiasts clarify these for me

[Mahiyammahi]

Op theoretically it's possible to break Bitcoin Security with Quantum Comouter but in reality it's nowhere near . You may come across some fancy article about breaking Bitcoin security in 9 minutes using Quantum Computer. Well bitcoin uses a system called eliptic curve cryptography and the private key consist 256 binary digits. So the total number of possible private keys are 2²⁵⁶ = 10⁷⁷

To give you real world Comparism for the size
Grains of sand on all Earth's beaches is only - 10¹⁹
Stars in observable universe - 10²⁴
Atoms in the observable universe - 10⁸⁰

Fastest Super Computer available rn only can do 10¹⁸ calculation per second but to break through this they would have needed 10⁵⁹ , shockingly our universe is only 10¹⁷ seconds old.

For a 500000 Qubits Super computer it would only take 9 minutes to break through the bitcoin security but don't fall for it this kind of technology doesn't exist. Maximum Qubits available for supercomputer in market is 100-1500 Qubits. Which is nowhere near .

Also an individual or a group of people can't arrange enough powerfull supercomputer to break through bitcoin , it would atleast need a contribution of a whole nation together resources. Which is a silly option. To spent a nation resource only doing this is just unacceptable.

Summary - in current power of supercomputer it's not enough in practically to break through bitcoin security. Also the developers all around of bitcoin ain't just sitting there to watch bitcoin shattering. They would definitely come across to save the ecosystem.


Source you may follow -
1. https://www.coindesk.com/tech/2026/04/18/how-a-quantum-computer-can-be-used-to-actually-steal-your-bitcoin-in-9-minutes
2. https://quantumzeitgeist.com/how-much-do-quantum-computers-cost/
3. https://www.quantinuum.com/blog/introducing-helios-the-most-accurate-quantum-computer-in-the-world

[Cookdata]

U have been reading  about quantum computing and i have occasionally come
Across claims that it could one day breaks the crypto graphic algorithm used by
Bitcoin. As a beginner, i want to understand what that will means In practice

Bitcoin has private key and corresponding public key for each address, when an address received Bitcoin, the Bitcoin is lock on the public key hash as script and you need the private key to unlock that script to spend the bitcoin but the public key will remain hidden. Once that coin is spent, the public key becomes visible on Bitcoin network.

The catch about Quantum computers is that it can calculate public keys to get real private keys of any wallet address and if it contains Bitcoin, they will be able to spend the Bitcoin on that address. There are many wallet address with public keys exposed on the Bitcoin network, if Quantum computers becomes real, it can wipe the entire wallet and spend them.

For now, there is are different proposal and some developers are working on how to move forward with Quantum threats but haven't been finalize. But as a bitcoin user, the only way to protect your self from Quantum computers is don't reuse wallet address when you spend Bitcoin, spend the coins on one transaction to new address, your public key will be exposed once you carried out a single transaction from an address.

   If the quantum computers becomes capable of breaking bitcoins security
Would bitcoin holders have enough time to move their coin to quantum resistance addresses
 Could bitcoins network be upgraded to defend against such threaten
Would older wallet be more vulnerable than the new ones
I would be glad if crypto enthusiasts clarify these for me

Like I said, there is ongoing discussion and proposals on how to handle Quantum threats. J. Lopp's Post-Quantum Migration BIP This was the last proposal by Jameson Lopp but it was controversial due to the fact that he proposed for Satoshi coins to be locked.

If Quantum computers algorithm becomes powerful, there will be an upgrade for everyone safety for sure.

[pawanjain]

U have been reading  about quantum computing and i have occasionally come
Across claims that it could one day breaks the crypto graphic algorithm used by
Bitcoin. As a beginner, i want to understand what that will means In practice
   If the quantum computers becomes capable of breaking bitcoins security
Would bitcoin holders have enough time to move their coin to quantum resistance addresses
 Could bitcoins network be upgraded to defend against such threaten
Would older wallet be more vulnerable than the new ones
I would be glad if crypto enthusiasts clarify these for me

A quantum computer can break bitcoin's security, yes, but it will take huge amount of time for it to do so.
Current quantum computers are not even close to breaking the bitcoin security and it will take a huge amount of power and resources in future to create such a quantum computer that can crack bitcoin address.
I believe by then, the developers will introduce a quantum proof bitcoin protocol that can keep our funds safe.
The best approach to tackle this situation until then would be to keep changing bitcoin addresses so that our funds are safe.