Bitcoin Difficulty Drops 2.3% as Hashrate Falls Below 1 ZH/s

Bitcoin’s network just cut its difficulty by 2.3% at block 947520 on May 1, 2026, the sixth downward adjustment of the year and the second epoch in a row to ease the work required to mine a block. Hashrate has fallen below the 1 zettahash per second mark, block intervals on May 3 are running at 10 minutes 28 seconds, and the next epoch on or around May 17 is now estimated to chop another 8.8% off, the largest cut yet in 2026.

Difficulty now sits at 132.47 trillion. The 24-hour hashrate band on Sunday ranged between 899 EH/s and 958 EH/s, well off the 1,000 EH/s peak the network briefly held before drifting lower from April 19. Hashprice climbed to $37.52 per PH/s as the adjustment landed, easing the pain for operators still online. Underneath that small recovery, the bigger story is a structural exodus of public miners who sold a record 32,000 BTC in Q1 to bankroll their pivot into artificial intelligence data centers.

The Numbers Behind the Sixth Cut of 2026

Six of the year’s nine difficulty epochs have now resolved downward, an unusually one-sided run for a year not following a halving. The May 1 epoch followed the April 17 cut of 2.43%, stacking back-to-back reductions for the first time since the mid-2024 capitulation window. Network hashrate, after touching the round 1 ZH/s milestone earlier in the spring, has spent the past two weeks below it.

• 132.47 trillion: the new difficulty target, locked in at block 947520 on May 1.
• 899 to 958 EH/s: the 24-hour hashrate range on May 3, comfortably under the 1,000 EH/s ZH-bar.
• 10 minutes 28 seconds: the average block time on May 3, 4.7% slower than the protocol’s 10-minute target.
• 1,877 blocks: the gap remaining before the next adjustment window opens around May 17.

Why Hashrate Slipped Below 1 ZH/s

Computational power did not collapse. It drifted. The seven-day simple moving average has been bleeding down since April 19, when the chart first turned. Operators have not flipped a single switch; they have been quietly de-energizing rigs that no longer earn their power bill.

The squeeze is documented in CoinShares’ Q1 2026 Bitcoin mining report, which estimated that 15% to 20% of the global fleet was running at a loss as hashprice scraped a five-year low near $28 per PH/s per day in February. Any rig less efficient than an Antminer S19 XP, paying 6 cents per kilowatt-hour or more, was burning cash to produce coins.

That math gets uglier when the BTC produced cannot service the debt that bought the rigs. Public miners spent late 2024 and 2025 levered into a price thesis that did not deliver in early 2026, and the only liquid asset on the balance sheet was the BTC itself.

So they sold. A lot. Public Bitcoin mining companies offloaded roughly 32,000 BTC during Q1 2026, a quarterly sell-off larger than the previous record set during the Terra-Luna unwind in mid-2022, according to data compiled across miner 10-Q filings and tracked by analysts at S&P Global Market Intelligence’s February research note on the AI and HPC pivot.

Some of those coins funded payroll. Most of them funded data centers. Capital that used to chase next-generation ASICs now chases GPU racks, liquid cooling loops, and 1.5-gigawatt power contracts.

Pool Concentration Tightens at the Top

The shrinking pie is being split by fewer hands. Over the trailing seven days the network produced 987 blocks, and three operators found 575 of them between them. Foundry USA alone closed 311, a 31.51% slice of the week, with Antpool at 16.51% and ViaBTC at 10.33%.

That 58.35% combined share is the kind of figure that makes Bitcoin’s decentralization advocates nervous, and it sits inside a wider field of 115 distinct pools currently contributing hashrate. The long tail is real, but the top is heavy.

Foundry’s run is consistent with its longer trend on the mempool.space Foundry USA pool dashboard, where the Digital Currency Group subsidiary has held the top slot for most of the past 18 months. The Hashrate Index pool concentration tracker shows the same Foundry-Antpool duopoly tightening as smaller US-listed miners reroute their hashrate to whichever pool offers the cleanest payout terms during a margin squeeze.

Hashprice Climbs, Margins Still Bleeding

The lift in hashprice from $34.39 to $37.52 per PH/s is real money for an operator running 100 PH/s, roughly an extra $313 a day. But it does not undo the damage of February.

Hashprice now sits in the bottom quintile of its five-year range. Operators who weathered the worst of the post-halving cycle are not popping champagne over a single epoch’s lift; they are calculating how much runway it buys.

A sustained downturn could force miners to shut down unprofitable rigs, and if prices were to stay below $80,000 for the remainder of the year, the hashprice would more likely flatline as weaker operators exit the network.

That assessment came from James Butterfill, head of research at CoinShares, in the firm’s Q1 2026 mining report. Butterfill’s framing matters because it puts a price floor under the question of when the bleeding stops, and it explains why the May 17 cut is being modeled as larger than the May 1 one.

The other shoe is the cost side. Public miners are reporting a per-coin production cost above $90,000 once depreciation, debt service, and corporate overhead are folded in. Below spot, that gap is funded by selling treasury or by raising new debt against AI infrastructure.

Core Scientific’s CEO Adam Sullivan, announcing the company’s $3.3 billion senior secured note offering on April 21, said the financing “provides liquidity and financial flexibility to accelerate development and commercial deployment of our high-density colocation and AI-focused data centers.” The phrase “Bitcoin mining” did not appear in the offering’s stated use of proceeds.

Block Times and the May 17 Adjustment Window

Block intervals are the leading indicator. At a true 10-minute average the difficulty algorithm holds steady; anything north of that, and the next epoch eases.

The current 10:28 average is 28 seconds slow per block, which compounds to roughly 87 minutes of slippage across the 2,016-block epoch. Newhedge’s Bitcoin difficulty adjustment estimator currently projects the May 17 epoch to drop the target from 132.47 T to 120.80 T, an 8.8% cut that would be the steepest of 2026 and one of the largest non-halving adjustments since the China mining ban summer of 2021.

1. April 17: Difficulty epoch reduces target by 2.43%, the fifth cut of the year.
2. April 19: Hashrate seven-day SMA turns down from above 1,000 EH/s.
3. May 1: Block 947520 lands the 2.3% reduction; difficulty resets at 132.47 T.
4. May 3: 24-hour hashrate band 899 to 958 EH/s; block time 10:28.
5. May 17 (estimated): Next epoch projected to cut difficulty an additional 8.8%, to 120.80 T.

The AI Pivot Reshaping Mining Capacity

The hashrate decline is not random attrition. It is a deliberate reallocation. Listed miners may derive as much as 70% of their revenue from AI and high-performance computing by the end of 2026, up from roughly 30% today, with more than $70 billion in AI and HPC contracts already inked across the sector.

Core Scientific is converting its Pecos, Texas campus into a roughly 1.5-gigawatt AI data center. Bitdeer reduced its BTC treasury to zero in February. Marathon, Riot Platforms, and Cango each disclosed material BTC sales tied to capacity repurposing or debt reduction. The capital is not coming back to ASICs.

That is why the May 17 adjustment carries weight beyond a routine epoch. A nearly 9% drop in difficulty, on the heels of two consecutive cuts, would mark the network’s loudest acknowledgement yet that its operator base has shrunk and concentrated.

For the miners still pointing rigs at SHA-256, the math finally tips toward survival. A 13% combined easing across April, May, and the projected mid-May epoch is worth more than $4 a day per PH/s at constant price, the kind of relief that keeps a marginal Texas warehouse online for another quarter.

Frequently Asked Questions

What is the next Bitcoin difficulty adjustment date in May 2026?

The next adjustment is projected for May 17, 2026, around 10:35 UTC, occurring at the end of the current 2,016-block epoch. Newhedge’s estimator currently models a drop from 132.47 trillion to roughly 120.80 trillion, an 8.8% cut. The exact timing depends on how block intervals trend across the remaining 1,877 blocks.

Why has Bitcoin’s hashrate dropped below 1 ZH/s in 2026?

Hashrate fell because public miners are de-energizing older rigs that no longer cover their power costs and are reallocating capital to AI and HPC data centers. CoinShares estimates 15% to 20% of the global fleet is unprofitable at current hashprice, and several listed operators have liquidated BTC treasuries to fund the transition rather than buy more ASICs.

What does a 2.3% Bitcoin difficulty drop mean for individual miners?

A 2.3% reduction means each unit of hashrate now finds blocks slightly faster, lifting expected revenue by roughly 2.3% at constant price and fee level. For a 100 PH/s operation at the current $37.52 hashprice, that translates to about $86 of additional daily revenue, useful but not transformative for rigs already underwater on power costs.

Is Foundry USA’s 31.51% mining share dangerous for Bitcoin?

Concentration matters because a single pool above 50% could theoretically reorder transactions, but Foundry USA at 31.51% is well short of that threshold. The combined top-three share of 58.35% is closely watched, though Foundry’s pool is composed of many independent miners who can repoint hashrate within hours if pool policies deviate from network norms.

How much BTC have public miners sold in 2026?

Publicly listed Bitcoin mining companies sold approximately 32,000 BTC during the first quarter of 2026, exceeding their combined net sales for all of 2025 and surpassing the prior quarterly record of about 20,000 BTC set in Q2 2022. Proceeds funded AI infrastructure buildouts, debt reduction, and operating costs.

Will Bitcoin’s network security suffer if hashrate keeps falling?

Network security depends on the cost of attacking the chain, not the absolute hashrate number. Even at 900 EH/s, attempting a 51% attack would require deploying hundreds of millions of dollars in ASICs and securing equivalent power, a barrier the protocol’s automatic difficulty adjustments help maintain by re-pricing the work needed per block as participation rises or falls.

The May 17 epoch will be the cleaner read on whether this is a pause or a phase change. If difficulty drops anywhere near the projected 8.8%, it confirms that capital is leaving SHA-256 faster than new ASICs are being plugged in. The hashprice lift to $37.52 may keep enough rigs online to muddy that signal for one more epoch, but the operator base behind those rigs is unmistakably smaller than it was six weeks ago.