Bitcoin climbed back near 69,500 dollars on August 20, and the money followed. Spot bitcoin ETFs pulled in 517 million dollars that day, the largest single session since early May, with BlackRock's fund taking 285 million of it. The price chart looked like a recovery. The machines that actually secure the chain were telling a slower story, because Bitcoin difficulty had just done something it has managed only once before.
The only earlier drop followed China's 2021 ban
By the start of August the network's difficulty sat near 126 trillion, down about 19 percent from its November 2025 record of 155.97 trillion and 14 percent below the peak it set in January, according to CoinDesk. The year-over-year line was the part worth stopping on. Bitcoin difficulty was running 1.1 percent under the 127.62 trillion it reached twelve months earlier. That is only the second time in the network's history that the figure has fallen below where it stood a year prior.
The first was the summer of 2021, when China evicted its miners and roughly half the network went dark inside a few weeks. This time nobody was banned. The rigs are leaving on their own.
Miners found a better customer
Hashrate, the raw computing power aimed at the chain, sits around 17 percent below its late-2025 high. It ran above one zettahash per second at the top. Through the summer it drifted between 850 and 920 exahash, news.bitcoin.com reported. The cause shows up plainly in miner earnings.
Listed miners now hold more than 70 billion dollars in contracted AI and high-performance computing work, and Hut 8 alone has booked 26.6 billion of that. CoinShares expects the AI side to supply about 70 percent of public miners' revenue by the end of 2026, up from roughly 30 percent in its previous report. The pull is easy to understand once the arithmetic is on the table. As recently as late March, miners were losing an estimated 19,000 dollars on every coin they produced, with weighted cash costs sitting near 80,000 dollars against a lower spot price. A rack that used to hash for bitcoin now rents to a model trainer, and it pays better. Some operators went further and started selling the coins they mine.
| Metric | Reading | When |
|---|---|---|
| Difficulty vs November 2025 record | down about 19 percent, 155.97T to near 126T | early August 2026 |
| Difficulty vs one year earlier | 1.1 percent lower, under 127.62T | first yearly drop since 2021 |
| Hashrate vs late-2025 peak | about 17 percent lower, 850 to 920 EH from above 1 ZH | summer 2026 |
| Hashprice | 27.66 to 31.70 dollars per petahash a day | late June to August |
| AI and HPC share of listed-miner revenue | near 70 percent projected, from about 30 percent | end of 2026 |
A leaner network as the price climbs
Hashprice, the daily revenue a miner earns per unit of power, fell to 27.66 dollars per petahash in late June, close to the lows it set in February. It has since recovered to about 31.70 dollars, and the forward market prices roughly 31.85 through December. That is thin enough that a single two-week reset in Bitcoin difficulty decides who keeps the power on. The August move lifted spot prices and the Treasury buyback rally brought ETF flows back, yet none of it has pulled hashrate toward its old record. A leaner network is also a more concentrated one, the kind of problem Zcash ran into this month when a single firm came to hold 18 percent of its mining power.
The next difficulty adjustment is due in the final days of August. Another downward print would stretch the distance between Bitcoin's price and the power behind it into a third straight period, and the operators still running rigs will keep sending them wherever the invoice is larger.
