Public miners shed 21% of BTC hashrate

TLDR

Publicly listed Bitcoin miners have cut about a fifth of their fleets hashrate as several shift capacity from mining to AI and high performance computing.

1. A cohort of major public miners reduced realized hashrate by roughly 21 percent over two quarters while ramping data center and AI revenue.
2. The overall Bitcoin network hashrate is down less than public miners share, so security remains strong but mining economics are clearly under pressure.
3. The key watchpoints are further AI pivots, post halving profitability, and any debate about how Bitcoin should adapt if industrial mining keeps shrinking.

Deep Dive

1. Scale And Drivers

According to a recent Miner Weekly report, a tracked group of public miners produced 368.3 EH/s of realized hashrate in Q4 2025, falling to 319.0 EH/s in Q2 2026.

Excluding Bitdeer, which expanded aggressively, the rest of the cohort dropped from 324.6 EH/s to 255.9 EH/s, a 21.2 percent reduction. That is the basis for the 21 percent hashrate shed headline.

Companies like Core Scientific and TeraWulf now earn most of their revenue from colocation and AI or HPC leases rather than Bitcoin mining, reflecting better returns per megawatt in GPU workloads than in post halving hashpower.

2. Impact On Bitcoin Security

Over the same period, the Bitcoin networks quarterly average hashrate fell from 1,071 EH/s to 957 EH/s, about a 10.6 percent decline, meaning non public or expanding miners offset part of the cut.

At these levels the network still has very high aggregate hashrate, so block production and proof of work security remain robust. The main impact is on miner margins and on who controls future expansion capacity, not on immediate consensus risk.

If industrial miners keep reallocating power to AI, security will depend more on a mix of smaller operators and on transaction fees rising enough to justify ongoing investment in ASICs.

3. Signals To Watch Next

Three practical signals to monitor are

1. further earnings reports showing mining versus AI revenue shares,
2. network hashrate trends around future difficulty adjustments and halvings, and
3. any renewed protocol debates about miner incentives.

If hashrate stabilizes while private or smaller miners fill the gap, the pivot may be mostly a rotation in who mines rather than a structural weakening.

If hashrate and hashprice keep falling together, pressure will build for miners to seek higher fee environments, explore new geographies, or push for changes that preserve their economics without undermining Bitcoins monetary rules.

Conclusion

Public miners shedding about 21 percent of their hashrate highlights how aggressively large operators are chasing AI and HPC revenues when Bitcoin mining becomes less profitable.

So far the broader network has absorbed much of that shift, keeping security strong, but the balance between industrial mining, smaller operators, and fee income is becoming more important for Bitcoins long term resilience.