The affirmation danger calculator, created by the Software program and Bitcoiner engineer Jameson LOPP, is launched to the Bitcoin ecosystem (BTC) as a useful gizmo to grasp the protection of transactions in that chain.
This improvement permits quantifying the extent of certainty {that a} consumer can have when accepting a fee after a sure variety of confirmations within the community. In an ecosystem the place centralization of the mining and the computing energy of the nice swimming pools generate questions concerning the robustness of the system, this calculator presents a technical and exact method to Consider the dangers of a double expense I’m not bitcoin.
LOPP is a related determine within the bitcoiner ecosystem for its deal with particular person safety and sovereignty. Lately, for instance, as Cryptonotics reported, he proposed an initiative to burn the BTC weak to quantum computing, arguing that this measure would shield the integrity of the community in opposition to future technological threats.
What’s the affirmation danger calculator and what’s it for?
The LOPP calculator, offered for the primary time in February 2023 in its private weblog, is a device designed to evaluate the chance {that a} confirmed transaction within the Bitcoin Community be reversed by a double expense assault. One of these assault happens when a malicious actor tries to rewrite the historical past of the block chain to cancel an already accepted transaction, spending the identical funds on one other operation.
The calculator primarily based on a mathematical mannequin that considers the share of hashrate (computing energy) managed by an attacker and the variety of confirmations that the transaction has acquired, thus providing a danger calculation to which the fee receiver faces.
LOPP underlines its sensible utility for retailers, exchanges and particular person customers who want to find out what number of confirmations are sufficient earlier than contemplating a definitive transaction.
LOPP was primarily based on Bitcoin Whitepaper
Historically, says the engineer Bitcoiner, the empirical rule of ready has been used Six confirmations to ensure a safety stage of 99.99%assuming that the attacker controls 10% of the worldwide hashrate.
Nevertheless, LOPP argues that this assumption, established in Bitcoin protocol and mirrored within the Satoshi Nakamoto Whitepaper, It’s not held within the present panorama. “These calculations have been made lengthy earlier than the invention of mining swimming pools and industrial mining operations. At the moment, it was affordable to imagine that it might be very troublesome for somebody to have greater than 10% of the worldwide hashrate,” writes LOPP, stating that since 2011 a number of entities have emerged with considerably greater participations.
At current, some mining swimming pools, similar to Foundry USA, Antpool, F2pool or Viaabtc, management amongst all 75% of the processing energy contributed by Swimming pools to the whole of the Bitcoin community, based on Mempool.Area.
The technical mannequin behind the calculator
The calculator relies on a probabilistic mannequin described in pages 6 and seven of Bitcoin Whitepaper, the place competitors is raised Between the sincere chain and the attacker’s chain as a “binomial random stroll.”
This mathematical idea describes a course of wherein every new block represents a step in a given course: if the block is generated by the sincere community (most hashrate), the benefit of this grows; If the attacker generates, his chain progresses and reduces the hole. Binomial nature comes from the truth that there are solely two attainable outcomes per spherical, and the possibilities rely upon the facility of relative computing.
Lopp explains it as follows: “The participant (attacker) is anticipated to lose more often than not, so the longer this recreation performs with a unfavorable anticipated worth, the much less doubtless it’s that it will likely be victorious.” Thus, with an attacker who has lower than 50% of the hashrate, the chance that he can attain and overcome the sincere chain decreases exponentially because the variety of blocks to be overcome will increase, a phenomenon that displays the safety inherent in Bitcoin’s design.
A concrete instance that LOPP stands out in its evaluation is the case of Foundry USA, one of many most important mining swimming pools that, on the time of the publication of the article (February 2023), managed 36% of the worldwide hashrate (32% at the moment). In line with their calculations, if a consumer accepted a fee after solely three confirmations, there was a 49% chance that Foundry I might rewrite the chain and execute a double expense.
Updating this evaluation with information from March 2025, the relevance of the LOPP calculator turns into much more evident. Drawing the identical equation, however with the present situations of the community, if a consumer accepted in the present day a fee after solely three confirmations, the chance that Foundry USA can perform that malicious conduct quantities to virtually 52%.
This enhance with respect to 49% calculated by LOPP in 2023, though Foundry now controls 32% of the hashrate, means that different components (similar to fluctuations within the whole hashrate or better potential coordination between Swimming pools) might be influencing the chance. This information, built-in to the LOPP mannequin, underlines how the Mining energy focus stays a crucial variable In 2025, reinforcing the necessity for instruments similar to this to regulate safety expectations to the truth of the community.
These calculations present how present mining dynamics have altered conventional safety notions. For instance, “the usual of six confirmations to succeed in 99.99% of certainty {that a} double expense won’t happen (assuming an attacker with 10% hashrate) now requires 60 confirmations to attain the identical stage of belief,” says LOPP.
Would a pool go in opposition to the Bitcoin Community?
The engineer additionally clarifies that this state of affairs doesn’t indicate an imminent or systemic menace to Bitcoin. The viability of such assaults is restricted by sensible and financial components. The mining swimming pools, LOPP particulars, are discouraged to carry out one of these maneuvers, since a profitable assault might undermine confidence within the community and, consequently, critically have an effect on your corporation.
Among the many causes for his or her confidence, it’s highlighted that industrial miners deepen their seek for low-cost power sources and distributed globally, in addition to technological advances similar to Stratum V2, which return some management to particular person miners in opposition to Swimming pools operators. On this sense, the function of Pool Ocean may be highlighted, which makes use of its personal Datum protocol, providing miners autonomy of their activity.
The affirmation danger calculator stays a mirrored image of Bitcoin’s dynamism, a community that, regardless of its strong foundations, should adapt to the realities of recent mining. The information of 2025 affirm that the dangers indicated by LOPP haven’t disappeared, however evolve over time, demanding customers with a extra exact understanding of safety.
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