Quantum computers powerful enough to break today’s encryption don’t exist yet, but the timeline is closer than most crypto holders assume, and it’s worth understanding which networks are actually prepared.
Why current encryption is exposed
Traditional computers process bits as a 0 or a 1. Quantum computers use qubits, which can represent multiple states at once, and that changes what’s computationally feasible. The 2048-bit RSA and elliptic curve encryption that secures most crypto wallets would take classical computers billions of years to crack. Using Shor’s algorithm, a sufficiently powerful quantum computer could theoretically solve the same problem in hours.
Dr. Michele Mosca, a quantum cryptography researcher, has put the odds of quantum computers breaking public key cryptography at roughly 1 in 7 by 2026, rising to about 50% by 2031. Other researchers think the timeline runs longer. There’s also a more immediate concern: encrypted transaction data can be harvested today and decrypted later, once the hardware catches up. That means data sent now isn’t automatically safe just because current computers can’t break it yet.
What makes a network quantum-resistant
Resistance comes down to using math problems that stay hard even for quantum computers. The National Institute of Standards and Technology has approved several post-quantum algorithms, including CRYSTALS-Kyber, as new standards. Bitcoin and Ethereum were built on RSA and elliptic curve cryptography, the exact schemes Shor’s algorithm targets. Upgrading either network would require coordinating a hard fork across thousands of stakeholders, a slow process with a real risk of community splits, as seen with Bitcoin Cash and Ethereum Classic.
How Hedera’s architecture differs
Hedera Hashgraph separated its consensus mechanism from its cryptographic layer, which means it can swap in new cryptographic standards without a network-wide hard fork. Its current hashing algorithm, SHA-384, is already considered resistant to Grover’s algorithm, the quantum attack most relevant to hashing, and meets government-grade security standards. Its signature scheme, Ed25519, is not yet quantum-resistant, but the platform is designed to swap it out once post-quantum standards are finalized, similar to replacing a component rather than rebuilding the whole system. That flexibility has attracted partners like SEALSQ, which builds quantum-resistant chips for satellite systems on Hedera’s network.
Hedera isn’t the only project thinking about this. Quantum Resistant Ledger built quantum resistance in from day one using XMSS signatures, though its ecosystem is far smaller than established platforms. Algorand uses Falcon signatures to secure its blockchain history every 256 blocks, which protects past transactions but doesn’t address future ones on its own.
What this means going forward
Current quantum computers have around 1,100 qubits. Estimates suggest running Shor’s algorithm effectively against modern encryption would take roughly 20 million. That’s a meaningful gap, but quantum research funding from IBM, Google, and governments is accelerating, and the timeline could compress faster than expected. For anyone evaluating long-term crypto exposure, a network’s ability to upgrade its cryptography without a disruptive fork is a factor worth weighing alongside the usual considerations of adoption and utility. This is not a prediction about which assets will outperform, just a look at which architectures are built to adapt.
Educational only, not tax, legal, or investment advice. Check primary sources and speak with a qualified professional before making financial decisions.
