Is it possible to calculate the odds of a single miner mining a BTC block
Since the beginning of September, three cases of finding a Bitcoin block by single miners have become known. Each of them mined the cryptocurrency on equipment with different computing power, which means that each one’s chances were significantly different.
A few days ago, one miner mined a block on equipment with a capacity of 61 Ph/s (petahash per second) – that's about 300 modern mining devices. According to calculations on the SoloChance portal, he has a chance of adding a block of 1 in 16 thousand each time he searches for a new block (every 10 minutes).
The odds of another miner finding a block with 200 Th/s (terahash per second) hardware were 1 in 100 years, or 1 in 4.8 million every 10 minutes. And late last week, a solo miner added a Bitcoin block to the blockchain on a single 4.8 Th/s device. His odds of success were an incredible 1 in 202 million.
An expert told RBC-Crypto how the probability of mining a bitcoin block is calculated during solo mining, and why this type of mining is closer to gambling than to serious business.
As of September 9, 2025, the difficulty of Bitcoin mining is about 136 T (trillion). This is a record level, which reflects the growing competition in the network: the more computing power miners connect, the higher the difficulty becomes, keeping the average time to find a block at 10 minutes, explained Anton Gontarev, Commercial Director of Intelion.
For a single miner, this means an extremely low probability of “catching a block,” the expert says. According to him, the mining process is mathematically described by the Poisson distribution: each ASIC miner participates in a kind of “lottery” where the chance of winning is equal to its share in the total global hashrate.
At the current global hashrate, a 200 Th/s device can only produce a block once every 90 years on average. For a 1 PH/s installation (approximately five modern devices), the average time is reduced to 18–19 years, for 10 PH/s — to one and a half years, Gontarev said.
He explained that the probability of an event occurring in a limited period of time can be calculated using the formula, where h is the miner's hashrate, H is the network hashrate, and 600 seconds is the average interval between blocks:
Formula for calculating the probability of an event in a limited period of time
For example, for a miner with 1 PH/s, the chance of finding a block in a week is about 0.1%, in a year – 5%. For 10 PH/s, the probability of a block in a year already exceeds 40%, the specialist noted.
He added that in practice, solo miners join services, such as the solo mining pool CKPool, which allows each connected participant to work “alone,” but through a common node. The combined hashrate of such miners is quite high, which is why “streaks of success” occur from time to time, as happened this month.
“These examples illustrate the dual nature of solo mining well. On the one hand, it is a lottery with an extremely small chance of success for an individual device. On the other hand, the combined pool of “loners” on a network scale still mines several blocks per month, and the stories of “little winners” always attract attention to the industry,” says Gontarev.
In the context of solo pools, a “single miner” does not mean a miner with one device, it can also be an entire data center with a lot of equipment. For example, a miner who mined a block on September 1 using 61 Ph/s rented these capacities for mining.
Today's network complexity of 136 T makes solo mining more of a gamble than a predictable business, the expert added. However, according to Gontarev, it is this “lottery” that creates unique cases when individual enthusiasts receive a reward on par with the largest data centers.
Источник: cryptocurrency.tech
