Google: Quantum Tech to Break Bitcoin’s Cryptography by 2029

The cryptocurrency industry stands tall on the backbone of decades-old encryption methods, guarding a transparent yet secure system built on monumental engineering that promises long-term protection. 

However, recent breakthroughs reveal that advanced quantum computers are developing much faster than expected, jeopardising the very secure foundational infrastructure that digital assets rely on.

Quantum computers can solve complex mathematical problems much faster than today’s sophisticated computers, which could be exploited to unscramble conventional methods for encrypting digital information.

This spells trouble for the US$2tn global cryptocurrency market which is entirely based on blockchains secured by cryptography. 

While the technology remains largely experimental, there have been growing concerns in the industry recently. 

Shrinking timelines

A March 2026 research from Alphabet’s Google suggests that quantum computers may be able to break that cryptography sooner than previously expected.

The tech giant says that quantum computers capable of breaking encryption could arrive by as early as 2029. Experts previously believed the technology would take at least 10 more years for anyone to build a quantum computer powerful enough to crack modern security encryption. 

To keep this dangerous capability out of the hands of cybercriminals, Google safely verified its findings with the US Government using secure cryptographic proofs. 

The report adds: “To share this research responsibly, we engaged with the US government and developed a new method to describe these vulnerabilities via a zero-knowledge proof, so they can be verified without providing a roadmap for bad actors.”

Google is now urging the crypto industry to upgrade to quantum-resistant security ahead of a 2029 timeline, collaborating with major networks including the Ethereum Foundation and Coinbase to safeguard digital assets. 

Recent research from Citigroup and others also conclude that quantum computing, along with AI breakthroughs, compresses the time frame in which cryptocurrencies will become widely vulnerable to hackers. 

Exposing the keys 

The crypto industry relies on blockchain technology, a shared and transparent digital ledger that records transactions across decentralised networks.

They are secured by mathematical security systems to create public and private digital keys, which act like account numbers and secret passwords to verify ownership and authorise transactions.

Public keys become visible to everyone whenever crypto is transferred. While regular computers cannot use a public key to figure out a secret private key, powerful quantum computers could do so easily.

This capability would allow cybercriminals to forge digital signatures and steal funds. The threat is severe because blockchain transactions are permanent and cannot be reversed like traditional bank payments.

Bitcoin, which is the most popular cryptocurrency, is highly vulnerable as its 17-year history has left millions of public keys exposed. 

Research from 2025 estimates this vulnerability could affect up to 50% of the network. If a hacker successfully steals and dumps a massive amount of tokens, market prices could crash entirely.

Upgrading the networks

Despite the rising concerns, many experts believe it will take a few years before quantum computers can successfully crack blockchain security, giving the industry time to upgrade to new, quantum-resistant security systems.

However, executives warn that upgrading too early brings its own risks because the new technology is changing rapidly. 

Quantum-resistant digital signatures require far more data storage and bandwidth. These heavier data requirements could slow networks down and raise transaction costs, a major issue for blockchains with rigid capacity limits, like Bitcoin.

Zach Pandl, Head of Research at Grayscale, says he has confidence blockchains will ultimately address the issues.

He says: “There is an engineering challenge ahead, but there are engineering solutions already on the table.”

The upgrade process is exceptionally difficult for decentralised networks because no single entity is in charge, the entire community must vote and agree on technical updates.

Currently, none of the top 20 blockchains use quantum-resistant signature algorithms. Bitcoin developers and investors remain heavily divided over which specific solution to choose and when to implement it.

The Ethereum Foundation, which supports the blockchain that underpins the second-largest cryptocurrency, says it is targeting 2029 for full protection from quantum computing.

On the other hand, the Algorand Foundation is among the early movers. It published a post-quantum roadmap last month and plans to start supporting post-quantum accounts later this year. 

The foundation supports the Algorand blockchain, whose native token has a market capitalisation of around US$780m. 

While cryptocurrencies have redefined the future of money, they now face a race against time to ensure that quantum computing does not end it.

Ultimately, its survival depends on whether decentralised networks can agree to forge new locks before quantum technology takes the keys.