Can Crypto Survive the Quantum Computing Era?

Oct. 28, 2026, 12:41 p.m. PT

Crypto is based on trustless systems, and trust in those systems still comes from cryptography. Bitcoin, Ethereum, Stellar and most other major blockchains rely on math problems that today’s computers can’t practically solve. Quantum computers could change that. One potential challenge for cryptocurrencies is the possibility that sufficiently advanced quantum computers could compromise some of the public-key cryptographic techniques used today.

The question applies to payment-focused networks like Stellar as much as to Bitcoin. Holders who track the xlm price usd rarely think about the signature scheme underneath, but it is what protects their balance.

Why Quantum Computing Worries Crypto Developers

When a user sends a transaction, most users aren’t even aware of cryptographic signatures. They are presented with a wallet, a balance and a confirmation. Blockchains prove ownership behind the scenes using public and private keys. The private key is used to access funds, and the public key is used to verify that the transaction is valid.

The worry is that such quantum computers may eventually be able to undermine or crack some of the existing signature schemes. Many blockchain networks use elliptic-curve cryptography. For example, Bitcoin uses ECDSA with the secp256k1 curve and 256-bit private keys, providing approximately 128 bits of classical security. That is far beyond what a brute-force attack can break, but a quantum machine would not attack it the same way. A sufficiently large quantum computer might be able to derive a private key from a public key using algorithms such as Shor’s algorithm.