Researchers have reduced the estimated computing cost of a specialized quantum-safe Bitcoin transaction to $59, an 82% drop from the roughly $320 estimate recorded during an August demonstration. The result comes as developers examine ways to protect millions of bitcoin whose public keys may already be exposed to a future quantum-computing attack. According to CryptoSlate, the latest figure is still a simulated, hardware-dependent estimate rather than the cost of a completed production transaction.
Optimization challenge drives lower estimate
The figures come from the Quantum-Safe Bitcoin Optimization Challenge, a public competition organized by StarkWare, Yukon Research and Eigen Labs. The project is focused on improving the calculations required by Quantum-Safe Bitcoin, or QSB, a method designed to protect specially prepared bitcoin holdings without immediately changing Bitcoin’s underlying consensus rules.
The projected cost has fallen sharply during the competition. StarkWare’s first mainnet demonstration in August produced an estimate of about $320. That figure declined to $67 in September and reached $59 by October 13. Researchers attributed the improvement to advances in graphics processing software and the use of AI-assisted coding tools to accelerate computational searches.
The latest benchmark produced more than 1 billion verified candidates per second on an Nvidia RTX 4090 graphics processing unit. The initial rate was approximately 146 million candidates per second. StarkWare said the progress has made its proposed emergency protection method significantly less expensive to prepare, while researchers are targeting a computing cost below $10.
The $59 number should not be treated as a final transaction price. It is based on simulated GPU workloads, and some computational stages still depend on provisional assumptions. Bitcoin network fees are not included. The researchers also still need to demonstrate the latest savings through complete transactions rather than benchmarks alone.
Why quantum computing matters for Bitcoin
Bitcoin relies on cryptographic systems to prove ownership of coins. A sufficiently capable quantum computer could potentially undermine the elliptic-curve cryptography used by Bitcoin by deriving private keys from exposed public keys. Private keys are needed to authorize spending, so such an attack could threaten coins whose corresponding public keys are visible on-chain.
The concern has become more prominent as researchers revise estimates of the computing resources that a future attack might require. In March, Google Quantum AI reported that, under specified hardware assumptions, attacks against elliptic-curve cryptography could theoretically be completed in minutes with fewer than 500,000 physical qubits. That estimate was about 20 times lower than earlier projections, although quantum computers with those capabilities have not been publicly demonstrated.
A Glassnode study cited in the report estimated that around 6.04 million BTC, or 30.2% of Bitcoin’s issued supply at the time, had exposed public keys. About 1.92 million BTC were exposed through their underlying address structures, while another 4.12 million BTC were exposed through address reuse or previous spending activity.
QSB is intended as an interim safeguard. It uses hash-based cryptography together with a computational puzzle, allowing holders to perform required calculations off-chain before spending coins. The method is designed for eligible holdings whose conventional public keys remain hidden until the coins are moved into specially constructed outputs.
That limitation is important. Bitcoin that already has an exposed public key could remain vulnerable if a capable quantum attacker appears before the coins are moved into a protected arrangement. StarkWare continues to support a broader protocol upgrade as the longer-term solution, but the QSB work could provide an alternative while developers consider wider changes to Bitcoin’s cryptographic infrastructure.
Deployment barriers remain
Lower computing costs do not by themselves make QSB broadly usable. Although the transactions comply with Bitcoin’s consensus rules, ordinary network relay policies reject them. As a result, users would need to submit them directly to miners prepared to process nonstandard Bitcoin transactions.
MARA’s Slipstream service supplied that route during the August demonstration. Future use would require dependable access to miners as well as successful testing of the complete transaction process. Those practical requirements remain unresolved alongside the technical work.
The optimization challenge therefore represents progress toward a potential emergency measure, not a finished protection system. Researchers must verify that the $59 estimate holds in full transactions and establish a reliable way for eligible users to get those transactions confirmed. The competition’s stated target of reducing the computing cost below $10 could further improve the method’s affordability, but no final timeline was provided.
Current Bitcoin market picture
Moneyiar market data recorded at 20:49 on October 13, 2026, showed Bitcoin at $83,314.89. BTC was up 0.36% over the previous 24 hours but down 2.70% over seven days.
For context within the supplied market data, Quant was priced at $215.78, down 6.46% in 24 hours and 18.91% over seven days. Compound stood at $23.09, down 3.30% and 4.77% over those periods, while ApeCoin traded at $0.1511, down 1.08% in 24 hours and 3.96% over seven days.
