AI slashes quantum-safe bitcoin transaction cost by 79%
The cost to execute a quantum-safe Bitcoin transaction has plummeted by nearly 79% in just one week, a dramatic development in the race to secure the world’s largest cryptocurrency from future threats. A developer competition, supercharged by artificial intelligence agents, saw the estimated price of a single quantum-resistant transaction fall from around $320 to as low as $66.
This breakthrough is the result of the Quantum-Safe Bitcoin Optimization Challenge, a joint initiative by StarkWare, Yukon Research, and Eigen Labs. Launched on September 16, 2026, the challenge galvanized a global community of developers and AI to rapidly improve the efficiency of a proposed defense mechanism against quantum computers.
The quantum-safe Bitcoin optimization challenge and its stunning results
The competition centered on improving the GPU computation for Quantum-Safe Bitcoin (QSB), a design first proposed by StarkWare researcher Avihu Levy in April 2026. This method allows for the creation of quantum-resistant transactions without altering Bitcoin’s core consensus rules, making it a potential emergency safeguard.
Just a week after the challenge began, StarkWare reported the estimated computational cost had fallen to $67 on September 23, a figure that later settled at $66 according to Yukon Research’s live dashboard. The first-ever QSB transaction, mined on August 26, 2026, had an estimated compute cost of $320, requiring 3,100 GPU-hours to complete. The new efficiency makes the process far more accessible.
The performance gains were staggering. On a benchmark Nvidia RTX 4090 GPU, throughput for a key process called “pinning” jumped from 146 million to over 820 million verified candidates per second. Another task, “subset selection,” saw a tenfold increase from 62 million to over 620 million candidates per second. These optimizations were the product of 62 accepted improvements submitted by the community.
The looming quantum threat to bitcoin
This race against the clock is motivated by a serious, if distant, threat. A sufficiently powerful quantum computer could one day break the elliptic curve cryptography (ECDSA) that secures every Bitcoin wallet.
Using an algorithm developed by Peter Shor, such a machine could derive a private key from a public key, giving it control over the associated funds. While the recent Bitcoin rally has been driven by other factors, this underlying security risk remains a long-term concern for the entire industry.
The scale of the vulnerability is immense. According to recent analysis, approximately 6.04 million BTC—about 30.2% of the current supply—are at risk. These coins, valued at over $500 billion, are in wallets where the public key has been exposed on the blockchain, often through address reuse.
This includes 1.92 million BTC exposed by script type and another 4.12 million through repeated use of the same address.
Experts believe breaking Bitcoin’s current encryption would require a machine with around 13 million stable qubits, far beyond today’s capabilities; Google’s most recent processor has 105 qubits. However, the timeline is shrinking. Some firms like IonQ project they could have the necessary hardware by 2028.
The concern is so significant that European financial regulators have warned that “threats could materialise earlier than any viable commercial application.”
Harvest now, decrypt later
Even if quantum computers are years away, the danger is present. Adversaries can engage in “harvest now, decrypt later” attacks, where they copy vast amounts of encrypted blockchain data today. They can then store this data indefinitely, waiting for the day a quantum computer becomes available to crack it open, retroactively compromising transactions and privacy.
AI’s role in accelerating quantum resistance
The speed of the cost reduction highlights the transformative impact of artificial intelligence in cryptographic development. In a related effort over the summer, over 100 researchers using AI coding agents helped slash the computational benchmark for a quantum attack on both Bitcoin and Ethereum by 86% in just two months.
David McAlvany, CEO of Vaulted, noted the compounding effect of this technology. “Because AI does the work of the coders more effectively, more efficiently,” he commented. “What might have taken twenty years to get to effective quantum computing, I think is going to shrink dramatically.”
This rapid progress suggests that while analysts debate if Bitcoin targets $90k in the short term, the long-term security landscape is being reshaped by AI.
The optimization challenge proved that a combination of human ingenuity and AI-powered tools can produce results at a pace previously thought impossible. Developers used AI agents to write, test, and refine code, rapidly iterating on complex computational problems to find novel efficiencies. This human-AI collaboration is becoming a new paradigm for tackling the most difficult challenges in computer science.
From demo to viable emergency measure
The initial $320 cost of the first QSB transaction in August was a proof-of-concept. While a groundbreaking technical achievement, it was too expensive for widespread use. The work, engineered by Tomer Giladi and submitted via MARA’s Slipstream service, was a demonstration of the possible, not the practical.
The dramatic cost reduction changes this equation. As StarkWare stated, “A construction that costs a few hundred dollars per transaction is a demo. One that costs $67 is closer to something a holder with a large unexposed balance might reach for in an emergency.” While Bitcoin holds its price levels amid market fluctuations, the QSB provides a potential lifeboat for high-value, vulnerable coins.
StarkWare researcher Avihu Levy has described the QSB approach as a “last resort measure,” acknowledging its complexity. It is not intended to replace Bitcoin’s standard security but to offer an escape hatch for the most exposed assets in a crisis scenario. Now, that escape hatch is becoming cheap enough to be a credible part of the industry’s contingency planning.
Broader implications and the road ahead
The success of the QSB Optimization Challenge is a significant milestone in the broader field of post-quantum cryptography (PQC). It demonstrates that proactive, community-driven efforts can yield practical solutions to theoretical threats. It also serves as a powerful case study for the use of AI in accelerating security research and development.
However, the work is far from over. StarkWare is quick to note, “This effort does not make Bitcoin quantum-safe. It makes one emergency option cheap enough to keep on the shelf.” The long-term solution will require a more fundamental migration to quantum-resistant cryptographic standards, a process that is already underway across the digital landscape.
For now, the ability to perform a quantum-safe transaction for the cost of a nice dinner is a remarkable achievement. It provides a crucial tool in the defensive arsenal against a future threat, buying valuable time for the entire ecosystem to prepare for the day quantum computers become a reality.