Bitcoin: Mining Difficulty Reaches Highest Level in Seven Months

The Bitcoin network has just imposed a new challenge on its miners. On October 16, 2026, the mining difficulty increased by 5.92%, reaching 140.58 trillion at block 971,712. This is its highest level since March 5 and the third-largest increase recorded this year. This rise comes as the network's computing power surpasses one zettahash per second. However, behind this surge in activity lies a less favorable reality. Miners now need to mobilize more computing power to hope for the same rewards, while their income per unit of power remains under pressure.

In Brief

• Bitcoin's difficulty climbs by 5.92%, from 132.72 to 140.58 trillion.
• The network's hashrate exceeds 1 ZH/s again, indicating increased competition among miners.
• At constant computing power, this increase theoretically reduces the amount of bitcoins a miner can expect to produce per unit of time by about 5.59%, all else being equal.

Why Bitcoin's Difficulty is Rising Again

The latest adjustment marks a break from the relative stability observed in early October. On October 3, the difficulty had slightly decreased by 0.03%, to 132.72 trillion. This period allowed miners to benefit from a more favorable environment after a particularly rewarding September.

But the dynamics changed quickly. According to data from Mempool.space, the adjustment on October 16 occurred at 12:37 UTC. The difficulty then increased by 7.86 trillion, confirming the acceleration of competition on the network.

The contrast with the summer is notable. On August 23, Bitcoin's difficulty had dropped to 125.81 trillion. Since that date, it has rebounded by about 11.74%.

This increase is explained by the very mechanism of the protocol. Every 2,016 blocks, or approximately two weeks, Bitcoin automatically adjusts the difficulty to maintain an average interval close to ten minutes between blocks. When these are produced faster than expected, the protocol increases the difficulty.

Hashrate Exceeds 1 ZH/s and Intensifies Competition

The increase in difficulty accompanies the return of significant computing power to Bitcoin. According to Hashrate Index, the hashrate reached approximately 1,024.96 EH/s on October 16, thus crossing the symbolic threshold of 1 ZH/s.

This measure corresponds to an estimate of the computing power mobilized by miners. It does not represent a direct count of the machines connected to the network. The return above 1 ZH/s contrasts with the situation at the beginning of September. At that time, miners' revenues were increasing without causing an immediate rebound in hashrate, which remained around 934 EH/s.

This evolution suggests that some computing power has been reactivated or strengthened as economic conditions improved. However, it does not allow for a precise determination of how many new machines have been installed.

For the Bitcoin network, sustainably high computing power can increase the economic cost of an attack based on proof of work. For individual miners, it mainly means more intense competition to obtain a share of the available rewards.

Bitcoin Miners' Revenues Remain Under Pressure

The main problem lies not only in the difficulty. It also concerns the profitability of each unit of computing power. On September 16, the hashprice, an indicator measuring the estimated daily revenue per petahash per second, reached $37.56. It then exceeded $41 several times before falling back to $36.75 on October 16, according to data from Hashrate Index reported by Bitcoin.com.

To concretely measure this pressure, let’s take a miner with 100 PH/s. With a hashprice of $36.75, their theoretical gross income reaches about $3,675 per day. This amount does not constitute a profit. Expenses for electricity, operating costs, maintenance, and equipment depreciation must still be deducted.

The increase in difficulty adds an additional constraint. With unchanged computing power, and all else being equal, a 5.92% increase in difficulty reduces the expected BTC production by about 5.59% per unit of time.

This distinction is important: a 5.92% higher difficulty does not mechanically correspond to a 5.92% decrease in revenue. The price of Bitcoin, transaction fees, and the actual power utilized also influence the results.

The pressure on margins is not new. Since June, Bitcoin miners have already faced a degradation of their profitability, notably due to the weakness of the revenues generated by their equipment.

The Increase Could Accelerate Economic Arbitrage

Faced with this competition, not all operators have the same means. Those using newer machines and benefiting from cheap electricity can maintain an advantage over older installations.

For structures with high costs, a further degradation of the hashprice could impose difficult decisions: temporarily reduce activity, modernize equipment, or seek other sources of income.

Some companies are already considering redirecting part of their infrastructure towards artificial intelligence. As shown by a recent analysis from Cointribune on the financing of miners engaged in AI, this diversification, however, requires significant investments and does not guarantee an immediate improvement in results.

The current increase in difficulty is therefore not sufficient to conclude that miners are becoming overall less profitable. It rather confirms that the recovery of revenues can attract more computing power, which ultimately reduces the initial advantage of already active operators.

A New Adjustment Expected by the End of October

The coming weeks will allow us to measure the strength of the rebound. Bitcoin.com initially mentioned a possible additional increase of 14.24% around October 28. However, this forecast was based on the first blocks of the new calculation period.

It should be considered with caution. Estimates continuously evolve according to the speed of block production. During our consultation on October 17, ChainQuery displayed a significantly lower projection of 2.72%, after only 113 blocks out of the 2,016 needed. This projection is also provisional.

The next adjustment will occur at block 973,728. Until then, three variables deserve particular attention: the evolution of the hashrate, the hashprice, and the price of BTC. The 5.92% increase confirms that competition is intensifying on the network. But it does not predict the future profitability of miners. This will mainly depend on their ability to maintain sufficient revenues in the face of energy and material costs that do not automatically decrease with market fluctuations.