• Can Quantum Computing Crack Bitcoin?
• Introduction
• Why Bitcoin's Security Could Face a Quantum Challenge
• The Research That Changed the Conversation
• Governments Are Already Preparing
• John Preskill's Warning: Preparing Before the Quantum Era Arrives
• Blockchain Projects Preparing for a Post-Quantum Future
• Starknet
• Quantum Resistant Ledger (QRL)
• IOTA
• Algorand, Hedera, and QANplatform
• Can Bitcoin Upgrade Before Quantum Computers Arrive?
• What This Means for the Crypto Industry?
• Final Thoughts
• More Blog Posts
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Can Quantum Computing Crack Bitcoin?

Introduction

Quantum computing has long been hailed as the next major leap in computing power. Unlike classical computers that process information using binary bits, quantum computers use qubits, enabling them to solve certain mathematical problems exponentially faster than today's most powerful supercomputers. While this breakthrough could transform fields like medicine, artificial intelligence, logistics, and scientific research, it also introduces a new cybersecurity challenge - one that could reshape the future of cryptocurrencies.

For Bitcoin, the question is no longer whether quantum computing matters, but when the industry should prepare for it.

Recent advances in quantum research have reignited discussions about Bitcoin's long-term security. Governments are investing billions into quantum technology, cybersecurity experts are accelerating the transition to post-quantum cryptography, and blockchain projects are already exploring quantum-resistant architectures. Although today's quantum computers remain far from capable of breaking Bitcoin, the conversation has shifted from theoretical speculation to long-term preparation.

Why Bitcoin's Security Could Face a Quantum Challenge

Bitcoin's security relies on two core cryptographic technologies:

• ECDSA (Elliptic Curve Digital Signature Algorithm), which secures wallet ownership and authorizes transactions.
• SHA-256, the cryptographic hash function used for mining and securing the blockchain.

These technologies are affected very differently by quantum computing.

Before diving deeper, here's a quick overview of how quantum computing affects the different components of Bitcoin's security.

A sufficiently powerful fault-tolerant quantum computer could theoretically use Shor's algorithm to derive a private key from a publicly known Bitcoin key. If that ever becomes possible, an attacker could forge valid digital signatures and spend funds without the owner's permission.

However, Bitcoin's mining process tells a different story. SHA-256 is far more resistant to quantum attacks. While Grover's algorithm could theoretically speed up brute-force searches, it only provides a quadratic improvement rather than the exponential advantage that Shor's algorithm offers against public-key cryptography. As a result, Bitcoin's digital signature system - not its mining algorithm - is the primary long-term quantum concern.

The important distinction is that no quantum computer today possesses the scale, stability, or error correction required to perform these attacks. Current quantum processors remain experimental and are still many technological breakthroughs away from threatening Bitcoin's cryptography.

The Research That Changed the Conversation

For years, researchers believed that breaking Bitcoin's elliptic-curve cryptography would require millions of physical qubits, making the threat appear decades away.

That perception changed in 2026.

Researchers from Google Quantum AI, Stanford University, the Ethereum Foundation, and other institutions published new resource estimates suggesting that future fault-tolerant quantum computers may require significantly fewer resources than previously believed to attack Bitcoin's signature scheme. While the exact hardware requirements depend on architecture, error rates, and engineering assumptions, the findings indicate that the gap between today's quantum computers and cryptographically relevant machines may be smaller than earlier estimates suggested.

This research should not be interpreted as evidence that Bitcoin is about to be broken. Instead, it highlights why the industry should begin preparing well before such machines become a reality.

Another growing concern is "Harvest Now, Decrypt Later" (HNDL)-a strategy in which adversaries collect encrypted data today with the intention of decrypting it once sufficiently powerful quantum computers become available. While Bitcoin transactions themselves are public, the broader financial and digital infrastructure that supports the crypto ecosystem - including exchanges, custodians, communications, and enterprise systems - could all be affected if post-quantum migration is delayed.

Governments Are Already Preparing

The urgency surrounding quantum computing extends far beyond cryptocurrencies.

Recognizing both its transformative potential and its cybersecurity implications, the United States issued two major Executive Orders on quantum technology in June 2026.

One order focuses on accelerating the adoption of post-quantum cryptography (PQC) across federal systems to protect sensitive information against future quantum attacks. The second, Executive Order 14413, establishes a national strategy to strengthen U.S. leadership in quantum computing through research, commercialization, workforce development, manufacturing, and national security initiatives. It also launches the Quantum Computer for Application Development and Discovery Science (QC-ADDS) program, aiming to develop a scientifically useful quantum computer while ensuring the United States remains at the forefront of quantum innovation.

These initiatives send a clear message: the transition to a post-quantum world should begin long before quantum computers become capable of breaking today's cryptography.

John Preskill's Warning: Preparing Before the Quantum Era Arrives

Following the White House's Executive Orders on quantum technology, Dr. John Preskill, a theoretical physicist at Caltech and one of the pioneers of quantum computing, shared his perspective on what the quantum era means for cybersecurity.

Speaking to NBC News, Preskill emphasized that the greatest risk isn't simply building a powerful quantum computer - it's failing to prepare before one exists. He warned that if quantum computers become capable of breaking today's public-key cryptography before governments and industries complete their transition to post-quantum cryptography, the consequences could extend far beyond cryptocurrencies. Secure communications, online banking, digital identities, government systems, and critical infrastructure could all become vulnerable.

Preskill's message was clear: the cryptographic tools needed to defend against future quantum threats already exist. The challenge now is ensuring organizations adopt post-quantum cryptography well before quantum computers become powerful enough to compromise today's encryption standards.

His perspective reinforces a broader industry shift: the race is no longer just about building more powerful quantum computers - it's equally about upgrading the cryptographic foundations that secure the world's digital infrastructure.

Blockchain Projects Preparing for a Post-Quantum Future

While Bitcoin's transition to post-quantum cryptography will require broad community consensus, several blockchain projects are already exploring or implementing quantum-resistant technologies.

Starknet

Starknet has emerged as one of the most interesting examples of quantum-aware blockchain infrastructure. Its STARK proofs rely primarily on cryptographic hash functions rather than the elliptic-curve assumptions used by Bitcoin's signature scheme. Since known quantum algorithms provide far less advantage against hash-based cryptography, STARKs are widely regarded as having stronger long-term resistance to quantum attacks.

Combined with Account Abstraction, Starknet also enables wallet signature schemes to evolve more easily as new cryptographic standards emerge, making future upgrades significantly more flexible.

Quantum Resistant Ledger (QRL)

As its name suggests, Quantum Resistant Ledger (QRL) was designed specifically for the post-quantum era. Since launching in 2018, the network has relied on XMSS (eXtended Merkle Signature Scheme) instead of traditional elliptic-curve cryptography, while continuing to adopt newer post-quantum signature technologies.

IOTA

Unlike conventional blockchains, IOTA uses a Directed Acyclic Graph (DAG) called the Tangle. From its earliest research, the project incorporated hash-based signature schemes and explored post-quantum cryptographic principles as part of its long-term vision. This makes quantum resilience an important part of its security roadmap, particularly for Internet of Things (IoT) devices expected to operate for decades.

Algorand, Hedera, and QANplatform

Other blockchain networks are taking different approaches to quantum readiness.

• Algorand has explored integrating post-quantum digital signature technologies while maintaining compatibility with existing infrastructure.
• Hedera has publicly discussed future support for post-quantum cryptography through coordinated network upgrades backed by its governing council.
• QANplatform was built with post-quantum cryptography in mind, combining ML-DSA (formerly CRYSTALS-Dilithium) with Ethereum-compatible smart contracts to reduce migration complexity for developers.

Although each project follows a different strategy, they share a common objective: designing blockchain infrastructure that can evolve alongside advances in quantum computing.

Can Bitcoin Upgrade Before Quantum Computers Arrive?

One of Bitcoin's greatest strengths is its ability to evolve through community consensus.

Over the years, the network has successfully implemented major upgrades such as SegWit and Taproot, improving scalability, privacy, and efficiency without compromising decentralization. A future migration to post-quantum cryptography would likely follow a similar path - through years of research, testing, discussion, and broad ecosystem coordination.

Researchers have proposed several migration strategies, including introducing new address formats secured by post-quantum signature algorithms, hybrid signature schemes that combine classical and post-quantum cryptography, and phased transitions that allow users to gradually move their funds.

While no single proposal has been adopted, one thing is clear: planning early is far easier than reacting after cryptographically relevant quantum computers become available.

What This Means for the Crypto Industry?

For investors, developers, validators, and institutions, quantum computing should be viewed as a long-term infrastructure challenge rather than an immediate security crisis.

Bitcoin remains secure today, and no existing quantum computer is capable of compromising its cryptography. However, the latest research, combined with increasing government investment and the standardization of post-quantum cryptography, demonstrates that the industry cannot afford to ignore the issue.

Preparation will require collaboration across wallet providers, exchanges, protocol developers, infrastructure providers, and blockchain communities. Fortunately, the tools to build a quantum-resilient future are already emerging.

Final Thoughts

Quantum computing represents one of the most exciting technological breakthroughs of the coming decades - but it also challenges many of the cryptographic assumptions that secure today's digital economy.

For Bitcoin, the threat is credible but not imminent. Current quantum computers remain far from capable of breaking Bitcoin's cryptography, and there is still time for the industry to prepare. The real question is not whether Bitcoin can survive quantum computing, but whether the ecosystem can migrate to stronger cryptographic standards before the technology matures.

Governments have already begun preparing through national quantum strategies and post-quantum cryptography initiatives. Researchers continue refining resource estimates for future quantum attacks, while blockchain projects like Starknet, QRL, IOTA, Algorand, Hedera, and QANplatform are exploring architectures designed with quantum resilience in mind.

As blockchain technology continues to evolve, quantum readiness will become another defining milestone in building secure, future-proof digital infrastructure.

At Encapsulate, we believe the next generation of blockchain infrastructure won't just scale - it will also adapt. Quantum computing may redefine what's possible, but proactive innovation and thoughtful preparation will determine how securely the crypto ecosystem enters the quantum era.

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