A mining pool is a group of miners who combine their hash power and share block rewards proportionally to each member's contribution. Solo mining on Bitcoin is like playing a lottery with astronomically low odds per ticket. Pooling means steadier, smaller payments rather than the rare jackpot of finding a full block yourself.
What Is a Mining Pool?
3 min read
The short version
Solo mining Bitcoin is like buying one lottery ticket every 10 minutes and hoping to win a $200,000 jackpot. You might wait decades between wins. A mining pool is like 10,000 people buying tickets together and splitting every win. You get $20 frequently instead of $200,000 rarely. Same expected value, but you can actually plan around regular income instead of praying for luck.
How It Works
How pools work: (1) You point your mining hardware at the pool's server (stratum URL). (2) The pool assigns you "work" (a range of nonces to try). (3) You submit "shares" (valid partial solutions that prove you are working, even if they do not meet the full difficulty target). (4) When any pool member finds a valid block, the pool distributes the reward proportionally to shares submitted. Payout methods: PPS (Pay Per Share): get paid for every share regardless of whether the pool finds blocks. Pool takes on variance risk and charges higher fees (2-4%). PPLNS (Pay Per Last N Shares): paid only when the pool actually finds blocks, proportional to your recent shares. Lower fees (1-2%) but irregular payouts. FPPS (Full Pay Per Share): PPS plus a share of transaction fees. Most popular method in 2024. Major Bitcoin pools (2024): Foundry USA Pool (~30%), AntPool (~18%), ViaBTC (~13%), F2Pool (~12%). Top 4 pools collectively produce ~73% of Bitcoin blocks. This concentration raises decentralization concerns, though individual miners within pools can switch freely.
Earnings from a mid-size mining operation in a pool
You run 10 Antminer S21s (total: 2,000 TH/s = 2 PH/s). Network total: ~600 EH/s. Your share of network hash: 2 / 600,000 = 0.00033%. Daily block rewards: 144 blocks x 3.125 BTC = 450 BTC. Your expected daily share: 450 x 0.0000033 = 0.0015 BTC ($90 at $60K). With a pool (FPPS, 2% fee): you receive 0.00147 BTC/day ($88.20). Payout: daily to your wallet. Without a pool (solo): you would find a block approximately once every 3.2 years. When you do, you earn 3.125 BTC ($187,500) at once. Same expected value over decades, but impossible to run a business on multi-year gaps between income events. The pool makes mining a viable business rather than a gamble.
What People Get Wrong
Mining pools control Bitcoin
Pools coordinate hash power but individual miners choose which pool to join. If a pool acts maliciously (censoring transactions, attempting 51% attacks), miners can switch to another pool within minutes. The pool operator has influence over block construction but miners have the ultimate exit power.
Bigger pools pay more per hash
Expected earnings per unit of hash power are the same regardless of pool size (after fees). Larger pools find blocks more frequently but split among more members. Smaller pools find blocks less often but each member gets a bigger share. The math equalizes over time.
Pool mining is risk-free
You still bear: hardware depreciation, electricity costs, difficulty increases reducing per-hash revenue, and the risk that BTC price drops below your cost of production. The pool reduces variance (steadier payments) but does not eliminate the underlying business risks of mining.
Keep Reading
Sources & Further Reading
- Mempool.space Mining
Live dashboard showing Bitcoin mining pool market share and block production
- Braiins Pool (formerly Slush Pool)
The first Bitcoin mining pool, operating since 2010
Questions People Also Ask
- How do I choose a mining pool?
- Consider: fee structure (PPS vs PPLNS), fee percentage (1-4%), payout threshold and frequency, geographic proximity (lower latency = fewer stale shares), reputation, and pool hash rate (larger = more consistent, but supporting smaller pools helps decentralization).
- Can I switch pools freely?
- Yes, instantly. Change the stratum URL in your miner configuration and you are on a new pool within seconds. There are no lock-ups, contracts, or penalties for switching. This freedom is what keeps pools honest: miner exit is always one config change away.
- What are pool fees?
- Typically 1-4% of your earnings, deducted automatically from payouts. PPS pools charge more (they absorb variance risk). PPLNS pools charge less (you absorb variance). FPPS at 2% is the current standard for most major pools.