Bitcoin Wallets From Ledger, Trezor and Blockstream Survive a Quantum Signing Test

Your current Bitcoin hardware wallet might already have what it takes to fight off a quantum computer. In a November 5 research update, Bitcoin infrastructure firm Blockstream said existing devices can generate post-quantum signatures without needing brand-new hardware. The catch: it takes a while.

The original experiment, run on August 19, put five hash-based signature schemes through their paces on a stack of popular wallets. The lineup: Jade Plus, Trezor Safe 3, 5 and 7, two Ledger models, and the BitBox02 Nova. Every single one produced post-quantum signatures using the experimental implementations, according to Blockstream.

Speed is the trade-off. A compact SHRINCS configuration spitting out 324-byte signatures needed roughly 22 to 42 seconds to sign, with Jade Plus clocking the fastest run at 21.75 seconds. That's a glacier next to ordinary Bitcoin signatures, but it proves today's silicon can handle cryptography built to shrug off quantum attacks.

Here's why anyone cares. Bitcoin authorizes transactions with elliptic-curve cryptography, where a digital signature proves you control the private key behind the coins you're spending. A powerful enough quantum computer running Shor's algorithm could theoretically pull private keys out of exposed public keys and drain funds. No known quantum machine today comes close to breaking Bitcoin's production cryptography, but the wallet type matters: some addresses hide public keys behind hashes until coins move, while older addresses and certain modern output types leave them out in the open.

Blockstream's SHRINCS proposal swaps elliptic-curve math for hash-based signatures, and its compact design tackles a second headache — quantum-resistant signatures are usually much bigger, which means fatter transactions and more block space burned. A draft Bitcoin Improvement Proposal covering SHRINCS and its reference implementation has already been submitted.

The tests didn't deliver full quantum-resistant firmware or a working quantum-proof wallet. Bitcoin developers still have to weigh the scheme's security, implementation demands, transaction costs and fit with existing infrastructure. Rival proposals are floating different paths, including migrating or eventually restricting quantum-vulnerable coins, and recent leaps in quantum computing are turning up the heat on how fast Bitcoin should move.