New all-time high for Bitcoin’s mining difficulty: 134.7T, according to the latest data (primary source: BTC.com). The peak comes as the hashrate shows slight weakness compared to recent highs, compressing miners’ margins and reigniting the debate on centralization of hashpower.
According to the data collected by our editorial team, which constantly monitors the activity of the main pools and on-chain metrics, the last two weeks have seen a reduction in the active power reported by public nodes, accompanied by an increase in maintenance requests for older ASIC models. Industry analysts also note that the top five pools continue to hold over 50% of the total hashpower, a figure that confirms the pressure towards concentration and centralized governance.
Key Numbers (data updated as of September 7, 2025)
- Difficulty: 134.7 T
- Hashrate: declining from weekly highs; for details on 7/30 day averages, visit Blockchain.com
- Subsidy per block: 3.125 BTC + fees – the reward was reduced by 50% following the halving on April 20, 2024, which brought the block from 6.25 BTC to 3.125 BTC
- Average block time: ~10 minutes (protocol target; retarget occurs every 2016 blocks, approximately ~14 days)
Why Difficulty Rises While Hashrate Slows Down
The difficulty automatically adjusts every 2016 blocks to maintain the production pace. The latest increase reflects the implementation of more efficient hardware and growing competition among operators. In this context, the recent decline in hashrate from the highs may be linked to maintenance operations, temporary shutdowns in areas with high temperatures, or price thresholds that make it economically less advantageous to operate part of the installed power.
Mining Costs: Where Margins are Squeezed
With difficulty at its peak, operational efficiency becomes crucial. The main pressure points include:
- Energy: rates and volatility directly impact net revenue; contracts like PPAs and curtailment can help, although they require contractual commitments and capital investments.
- Capex hardware: the latest generation ASICs, although more efficient in terms of joules per terahash, have high initial costs and longer delivery times.
- Cooling and logistics: with rising costs during hot seasons and in regions with extreme climate, optimizing cooling systems – both through liquid and immersion technologies – becomes crucial to improve PUE.
For operators who do not benefit from economies of scale or competitive energy rates, profitability tends to approach the breakeven point.
Concentration of Hashpower: The Weight of Large Pools
With the increase in costs and investments in hardware, the major players in the sector are consolidating significant shares of the network. The concentration of hashpower in a few pools increases the risk of centralized governance and coordination in operational decisions.
- Top pool: for monitoring, consult MiningPoolStats.
- Risks: less diversification leads to greater reliance on a few entities for block propagation and fee policy definition.
- Mitigations: there is a push towards non-custodial pools, the adoption of the Stratum V2 standard (to reduce the risk of template centralization), greater geographical decentralization, and increased transparency in the templates used by pools.
Hashrate: short-term signals
The hashrate can fluctuate rapidly due to factors such as weather conditions, maintenance, the price of BTC, and energy availability. It should be noted that a brief decoupling between the increase in difficulty and the drop in hashrate is physiological, as the algorithm only accounts for these variations at the next adjustment.
BTC Price, Fees, and Profitability
With the block reward set at 3.125 BTC, the volatility of the price and the level of fees directly impact the margins. During periods when the mempool is congested, fees tend to increase, improving miners’ revenues, while strong price corrections can push some operators to shut down part of the less efficient power.
Small vs. Giants: Do “Solo Miners” Still Exist
Although rare, episodes of blocks found by solo miners continue to occur from time to time recently, as evidenced by some public dashboards. That said, the payout, being heavily dependent on chance, luck, and the level of fees, remains a sporadic event.
These events do not substantially impact the overall picture, as without economies of scale or access to competitive energy sources, the activity of small miners is more random than sustainable.
Energy and Geography: Where to Win
Facilities with access to stable rates, renewable energy sources, or the ability to exploit excess energy prove to be more resilient over time. Long-term agreements, such as PPAs, along with the use of curtailment and integration with local grids, help mitigate regulatory risk and cost volatility. For assessments on the energy impact of mining, you can refer to the Cambridge Bitcoin Electricity Consumption Index for updated data on consumption and the geographical distribution of mining activity.
Short-term Outlook: The Next Adjustment
The retarget algorithm, which intervenes every 2016 blocks, could alleviate the difficulty spike if the hashrate were to remain below recorded highs. Conversely, a rapid return of power online could resume the upward trend. Indeed, monitoring the average block time, fees, and block propagation remains essential to navigate future trends.
