Mining: Parameters, Economics and the Difficulty Mechanism

Entry last verified September 2026.

The mechanism

Miners repeatedly hash a candidate block header, varying a value inside it, until the result falls below a target. Finding one is proof that work was performed, since there is no method faster than trying.

The successful miner broadcasts the block and collects the subsidy plus the fees of the transactions included.

Difficulty adjustment

The target adjusts so that blocks arrive at roughly the intended interval regardless of how much hashing power is active.

Chain	Adjustment interval	Target block time
Bitcoin	Every 2,016 blocks, about two weeks	10 minutes
Litecoin	Every 2,016 blocks	2.5 minutes

If hash power rises, blocks arrive faster, and the next adjustment raises difficulty. If hash power falls, the reverse.

The consequence for miners is that adding capacity does not increase total rewards. It redistributes them, and the addition is competed away within one adjustment period.

The profitability equation

Revenue is the block subsidy plus fees, denominated in the mined asset, multiplied by the miner’s share of total hash power.

Costs are electricity, hardware amortisation, hosting, and financing.

The variables that matter:

Variable	Effect
Electricity price	Dominant operating cost, typically the majority
Machine efficiency, joules per terahash	Determines cost per unit of work
Network difficulty	Determines share of rewards
Asset price	Determines revenue in currency terms

A miner is a price taker on the output and a contract holder on the input. That combination is why margins compress violently when price falls.

The halving effect on mining

Each halving cuts subsidy revenue in half overnight. Operations with power costs above a threshold become unprofitable immediately.

The historical sequence: unprofitable capacity switches off, difficulty adjusts downward, economics improve for remaining operators, and capacity consolidates toward those with the cheapest power and the newest hardware.

The fee transition

As the subsidy approaches zero, fees must replace it or the network’s security budget shrinks.

Fee revenue currently spikes during congestion and subsides afterwards. Whether it forms a durable base sufficient to secure the network is unresolved and is the principal open question about the long-term model.

What miner behaviour indicates

Flows from mining pool addresses to exchange deposit addresses represent production being sold. Sustained increases indicate selling pressure from operations covering costs.

The inverse is more informative: miners holding production are financing operations by other means, usually equity or debt issuance, which says more about their access to capital markets than about their price view.

These flows are observable on-chain, and the destination addresses frequently belong to large venues including exchanges quoting a direct fiat pair, which is how analysts identify them.