Solo mining Bitcoin: what the odds actually look like

Guest post by Tom Bennet (bennet.org)

Every ten minutes, on average, someone somewhere wins 3.125 BTC plus fees. Whether that winner is a giant industrial miner or a lottery-style solo pleb, the mechanism is the same: it all comes down to who guesses the right number first.

Technically, you do not even need mining hardware to guess. In theory, you could mine Bitcoin with pen and paper, as long as you were patient enough to run SHA-256 by hand. The problem is that your hashrate would be hilariously low.

So what are the odds that a single guess successfully mines a block?

With Bitcoin difficulty at extreme modern levels, the probability of any individual hash winning a block is effectively microscopic. On the scale of human intuition, it is easier to think of a single hash as a lottery ticket with almost no chance of success on its own.

One useful analogy: a single hash is roughly like blindly selecting one specific cubic centimetre from an unimaginably vast volume of water. The odds are that small.

Why bother?

Because miners are not guessing once.

Modern miners make billions or trillions of guesses every second. That is what hashrate means. A terahash per second (TH/s) is one trillion guesses per second.

The odds are still tough, of course, but there is a huge difference between making one guess and making trillions of them every second, 24 hours a day.

For example, a NerdOctaxe Gamma runs at around 9.6 TH/s. That still does not make solo mining “likely,” but it puts you in the game in a way that pen-and-paper never could.

Move up to industrial hardware and the picture changes further. A modern ASIC at a few hundred TH/s still does not guarantee a block, but the odds become much less absurd. Scale that into petahash territory and solo mining starts to look less like fantasy and more like a volatile lottery.

And that volatility is the point. Bitcoin does not reward miners by seniority. Every hash is a fresh ticket. Someone running a tiny solo miner can get lucky. Someone with a much larger setup can still wait a very long time.

What has actually been happening

Solo mining is not just a theoretical curiosity. It happens.

In 2025, solo miners found confirmed blocks using a mix of setups, from consumer-focused devices to repurposed industrial ASICs. Different solo mining tools and platforms contributed to those wins, and the timing was highly uneven, exactly as probability would suggest.

Sometimes there are long droughts. Sometimes multiple wins happen close together. That variance is not unusual; it is the nature of solo mining.

My tracker below shows confirmed solo blocks since 2023, including timestamps, total rewards with fees, and the software used:

And if you want to explore the frequency and clustering of solo finds, this stats view makes the variance even more obvious:

Why this matters beyond the novelty

Bitcoin mining has spent years becoming more concentrated. A relatively small number of very large pools control a major share of global hashrate.

Solo mining does not reverse that trend on its own, but it keeps the long tail alive: more independent block producers, more self-sovereign setups, and more people participating without relying entirely on a dominant pool operator.

Every solo block is a reminder that Bitcoin is enforced by protocol rules, not by any single company or mining pool.

Devices like the Bitaxe Gamma matter not only because they hash, but because they normalize something bigger: running your own hardware, pointing your own hashrate, and taking part directly.

On the other end of the spectrum, older industrial ASICs are increasingly being repurposed by individuals and businesses. Some are used as heaters or for dual-purpose setups, where the heat is useful and the hashing becomes a kind of background lottery. That is one of the most entertaining aspects of solo mining: even practical hardware can double as a ticket printer.

Want to try your luck?

The solo mining calculator at Bennet.org lets you estimate the odds for your own hashrate, with presets for popular solo mining hardware.

If you are looking for hardware, you can browse solo miners available at Power Mining, including options like the Bitaxe Gamma and NerdOctaxe Gamma.

Someone is going to find the next block. The odds say it probably will not be you. Bitcoin does not care what the odds say.