Why miners pool hashrate, how payouts work and which centralization risks deserve attention. The explanation separates consensus rules from estimates about machines, energy, and mining economics.
- Pools reduce income variance rather than creating more block rewards.
- Payout methods allocate risk differently.
- Template construction matters for decentralization.
Smoothing variance
A small miner might wait years to find a block alone. Pools aggregate work and distribute revenue according to submitted shares, trading lottery-like payouts for smaller, more regular payments.
Payout models
Pay-per-share models shift variance to the pool and usually charge accordingly. Proportional and pay-per-last-N-shares methods distribute risk differently. Fees alone do not reveal the best option.
Name the layer and the actor. Wallets create transactions, nodes check rules, miners propose blocks, and Lightning peers manage channels.
Template control
Pools have traditionally selected block transactions, creating concentration concerns. Protocols that let individual miners construct templates can reduce that influence while preserving coordinated payouts.
Why pools exist
A single modern machine has one chance in several million of finding the next block; on its own it might wait years, then receive 3.125 BTC plus fees at once.
A pool combines the work of thousands of machines, finds blocks regularly, and pays each participant according to the work it contributed — measured in shares, partial solutions that prove effort without being valid blocks. The miner trades a lottery ticket for a steady wage and pays the pool a fee of one to a few percent.
Almost all hashrate is pooled, and a handful of pools find most blocks.
Payout schemes compared
Pay-per-share pays a fixed amount per share regardless of whether the pool finds a block, so the pool carries all the variance; fees are higher. Pay-per-last-N-shares pays out of actual block rewards according to shares submitted over a recent window, so miners carry variance and can be paid nothing during a dry spell; fees are lower.
Full-pay-per-share adds an estimate of transaction fees to the fixed rate. Most large pools offer FPPS. Whichever scheme, the pool's accounting is opaque unless it publishes its blocks and payouts; reputable ones do, and a miner can check that the blocks a pool claims to have found match the coinbase addresses on the chain.
Centralisation and Stratum V2
Pools decide which transactions go into the blocks their miners build, which puts real influence over ordering and censorship in a few operators' hands even though they cannot break consensus rules. Miners can switch pools in minutes, and have done so when a pool grew uncomfortably large, but the incentive to do so is weak.
Stratum V2, now supported by several pools and firmware, lets individual miners construct their own block templates and choose transactions themselves while still sharing rewards. It moves the decision back to the many machines from the few servers, which is why it matters more than its technical description suggests.
Check the mining claim against the rule
Separate facts fixed by block height and subsidy from estimates of hashrate, energy use, cost, and profitability. Record the assumptions behind every calculated figure.
Common questions
Why do miners join a pool?
To smooth income. A single machine might find a block once in many years; a pool combines many miners, finds blocks regularly and pays each participant in proportion to the work they contributed, in exchange for a small fee.
What do PPS, PPLNS and FPPS mean?
Payout methods. Pay-per-share pays a fixed amount for each unit of work regardless of luck; pay-per-last-N-shares pays from actual block rewards across recent work; full-pay-per-share adds transaction fees to the fixed rate. They trade variance against pool risk.
Do mining pools control Bitcoin?
Pools choose which transactions go into the blocks they build, but they cannot break the rules that nodes enforce, and miners can leave a pool in minutes. Stratum V2 goes further by letting individual miners select transactions themselves.
Sources and further reading
Primary documents this guide draws on. Links open the original publisher.
- Pooled mining Bitcoin Wiki
- Stratum V2 protocol Stratum V2 reference
- Developer guide: mining developer.bitcoin.org