Watch out Bitcoin devs. Google says post-quantum migration needs to happen by 2029.
The crypto industry's reaction was that a quantum computing threat was still distant when Google unveiled its Willow quantum chip in December 2024 .

Bitcoin uses SHA-256 for mining and ECDSA for signatures, both of which are theoretically vulnerable to quantum decryption, but the consensus was that the threat was decades away .
Breaking encryption would require millions of physical qubits (a unit of information in quantum systems).
Willow had just 105.
That story has marginally changed sixteen months later, and Google isn't dismissing anything.
The company announced this week that it is setting a 2029 deadline to migrate its authentication services to post-quantum cryptography, citing progress in quantum hardware, error correction, and factoring resource estimates.
These risks are not theoretical.
The Android 17 mobile operating system is already integrating post-quantum digital signature protection.

Chrome already supports post-quantum key exchange.
Google Cloud offers post-quantum solutions to enterprise customers.
Classical computers process information as bits, each one either a 0 or a 1, and solve problems by checking possibilities one at a time.
Quantum computers use qubits that can exist as both 0 and 1 simultaneously, a property called superposition, which lets them explore vast numbers of possibilities in parallel.
For most everyday tasks, the advantage is negligible.
But for specific problems like factoring the large prime numbers that underpin modern encryption, a sufficiently powerful quantum computer could solve in minutes what would take a classical machine longer than the age of the universe.
Bitcoin uses ECDSA (Elliptic Curve Digital Signature Algorithm) to sign transactions, which is exactly the category of cryptography Google flagged as requiring migration before a quantum computer capable of breaking it arrives.



