$75 of Rented Hash Power, 3.125 BTC Won: What a Solo Bitcoin Block Really Tells Us

A cheap asymmetric bet just paid out. Early Tuesday, a solo miner renting the minimum 1 PH/s of capacity on Braiins’ hashpower marketplace landed block 938092 and took home 3.125 BTC—just over $200,000—after spending roughly 119,000 sats (about $75). Braiins said the job carried zero hashpower fees and a 0.5% solo fee for CKPool’s open-source contribution. The worker label was “spiral.”

On the surface, that reads like luck. At 1 PH/s, the math implies success about once every 1.1 million blocks—or roughly once in 21 years at today’s network conditions, per SoloChance.com. But the more interesting takeaway isn’t the win; it’s why these convex wagers keep showing up in a market dominated by industrial hash.

The structure of proof-of-work still allows an individual to buy a small slice of the global lottery without owning a rig. Marketplaces like Braiins abstract away logistics—sourcing hardware, power, firmware—so the only decision is how much budget to place on tail outcomes. That simplicity, plus permissionless access, keeps the “lottery ticket” alive even as professional miners optimize for steady, low-variance cash flows in pools.

The salience is reinforced by a steady drip of headline jackpots. In January, two solo miners separately earned more than 3.1 BTC apiece—worth about $300,000 at that time. Another hit in December cleared north of $282,000. Each story resets the psychological reference point despite the odds trending harder. The network’s daily average hashrate sits above 1.1 ZH/s, according to Bitinfo, up from around 730 EH/s a year ago—about 61% of today’s capacity. Bigger denominator, thinner probabilities.

There’s also a market-structure shift underneath. North American pools saw their share of compute slip in 2025, while hash likely grew in China and other regions. Part of the reshuffle is strategic: miners that once chased BTC block rewards are redeploying toward AI workloads. Bitfarms is winding down mining altogether. Riot Platforms is being pushed by investors to capture AI economics. As large operators tilt toward steadier, higher-IRR compute, the gap between professional risk management and retail optionality widens. That gap is exactly where small solo punts live.

Economically, the expected value on a one-off solo rental is tiny and usually negative after fees and variance. But optionality isn’t about the mean. It’s about paying a capped cost for exposure to rare, system-wide randomness that remains credibly neutral—every nonce is a fresh draw. From an industry perspective, that’s a feature: proof-of-work preserves the possibility that any honest participant can win a block, which supports decentralization narratives even as mining industrializes.

None of this turns lottery mining into a strategy. Pools exist for a reason: they smooth cash flows, finance operations, and absorb variance. But the ability to convert 119k sats into a 3.125 BTC outcome—however improbable—keeps participation sticky and stories viral. It’s part marketing, part math, and part ethos.

Braiins publicized the win but did not immediately respond to a request for comment. The numbers speak clearly enough: tail events still occur, the network keeps hardening, and the market keeps bifurcating—professionalized pools on one side, on-demand convexity on the other. Both can coexist, and occasionally, someone renting 1 PH/s for an afternoon gets a reminder of why proof-of-work’s lottery never fully closes.