In this guide
How mining works
Mining is the process of using computers to validate transactions and add them to the blockchain. Miners collect pending transactions, bundle them into a block, and then race to solve a cryptographic puzzle. The first miner to find the solution gets to add the block and earns a reward.
For Bitcoin, that reward is currently 3.125 BTC per block (after the April 2024 halving). At $95,000 per Bitcoin, that's roughly $297,000 per block. A new block is found approximately every 10 minutes, so the network pays out around $43 million per day to miners collectively.
The "puzzle" isn't something miners solve with intelligence. It's brute force. They try billions of random numbers per second (called hashes) until one produces a result below a target threshold. It's like rolling a die and needing to get a 1, except the die has trillions of faces. Whoever rolls fastest has the best odds.
The difficulty automatically adjusts every 2,016 blocks (roughly two weeks). If blocks are found too quickly because more miners joined, difficulty increases. If miners leave, it decreases. This keeps the average block time at 10 minutes regardless of how much computing power is on the network.
Proof of work explained
Proof of work (PoW) is the consensus mechanism behind mining. The "work" is the computational effort miners spend trying to find valid hashes. This work is what secures the network. To attack Bitcoin, you'd need more than 50% of all mining power on Earth. That's currently estimated to cost over $10 billion in hardware alone, plus enormous ongoing electricity costs.
Bitcoin uses the SHA-256 hashing algorithm. Every attempt produces a 256-bit output that looks random. Miners try different inputs (nonces) until they find one where the hash starts with enough zeros. Finding this is hard. Verifying it takes milliseconds. That asymmetry is the whole point.
It's worth noting that Ethereum used to be mined but switched to proof of stake in September 2022. Bitcoin remains the biggest proof of work chain, and there's strong consensus in the Bitcoin community that it'll stay that way. Most other modern blockchains use staking instead.
Mining equipment
In Bitcoin's early days (2009-2012), you could mine with a regular CPU. Then GPUs took over because they're better at parallel processing. By 2013, ASICs (Application-Specific Integrated Circuits) arrived. These are chips designed to do one thing: mine Bitcoin. They're thousands of times more efficient than GPUs.
Today, mining Bitcoin with anything other than an ASIC is pointless. You'll spend more on electricity than you'll ever earn. Current-generation ASICs like the Bitmain Antminer S21 produce around 200 TH/s (terahashes per second) while consuming about 3,500 watts. A single unit costs $5,000-8,000.
Professional mining operations run thousands of these machines in warehouses (often in locations with cheap electricity like Texas, Wyoming, Paraguay, or Kazakhstan). They need industrial cooling, dedicated power infrastructure, and technical staff. This isn't a hobby anymore. It's a capital-intensive business.
GPU mining isn't dead though. Some smaller cryptocurrencies like Kaspa, Ergo, and Ravencoin can still be GPU-mined. But the profits are much smaller and the economics are tighter. If you already have a gaming GPU, you can try it to learn, but don't expect to get rich.
Profitability in 2026
The honest answer: for individuals, mining is rarely profitable unless you have cheap electricity (under $0.05/kWh) and are willing to invest $10,000+ in equipment. The math is simple but unforgiving.
Let's say you buy one Antminer S21 for $6,000. At current difficulty and Bitcoin price, it generates roughly $15-20 per day in revenue. Electricity at $0.10/kWh costs about $8.40 per day. So your profit is $7-12 per day, meaning it takes 500-850 days just to break even on the hardware. And difficulty keeps increasing as more miners join, which means your daily revenue shrinks over time.
The April 2024 halving cut the block reward from 6.25 BTC to 3.125 BTC. Revenue per unit of hash power was literally cut in half overnight. Miners with expensive electricity went unprofitable immediately. The next halving in 2028 will do the same thing again.
Large-scale operations with electricity at $0.03-0.05/kWh and thousands of machines are still very profitable. They have economies of scale that home miners can't match. Companies like Marathon Digital and CleanSpark are publicly traded and report strong margins.
My take: unless you have access to truly cheap power (solar, hydro, or wholesale rates), you're better off just buying Bitcoin directly. The math favors large operations, not garage miners.
Mining pools
Solo mining means you get the entire block reward (3.125 BTC) when you find a block. But the odds of a single ASIC finding a block are astronomically small. You might mine for years and find nothing.
Mining pools solve this. Thousands of miners combine their hash power and share rewards proportionally. If you contribute 0.001% of the pool's total hash rate, you get 0.001% of each block reward the pool finds. Steady, predictable income instead of a lottery.
The largest Bitcoin mining pools are Foundry USA, AntPool, F2Pool, and ViaBTC. Together, the top 4 pools control about 70% of Bitcoin's hash rate. This concentration is a centralization concern, though individual miners in a pool can switch pools anytime.
Pools charge fees, typically 1-2% of your earnings. Some use different payout methods: PPS (Pay Per Share) gives you consistent payouts regardless of whether the pool finds a block. PPLNS (Pay Per Last N Shares) rewards you based on actual blocks found, which is more variable but slightly more profitable long-term.
Environmental impact
This is the elephant in the room. Bitcoin mining consumes roughly 150 TWh of electricity per year, comparable to a medium-sized country like Poland. Critics say this is wasteful. Supporters argue it secures a trillion-dollar network and increasingly uses renewable energy.
The data is nuanced. The Bitcoin Mining Council estimates over 60% of mining energy comes from sustainable sources. Miners actively seek out the cheapest electricity, which is often stranded renewables: hydroelectric dams, solar farms, or wind turbines producing excess energy that would otherwise be wasted.
Some mining operations capture methane from landfills or oil wells, flared gas that would otherwise be released into the atmosphere. In these cases, mining actually reduces emissions. Companies like Crusoe Energy specifically build mining operations at flare sites.
But let's be real: if Bitcoin used proof of stake like Ethereum does now, it would use 99.9% less energy. The Bitcoin community's commitment to proof of work is philosophical as much as technical. They believe the energy expenditure is the price of true decentralization and censorship resistance.
Alternatives to mining
If mining doesn't make sense for you (and for most people it doesn't), there are easier ways to earn crypto:
Staking: Earn 3-8% APY by locking up your crypto to help secure proof-of-stake networks. No hardware needed.
Yield farming: Provide liquidity to DeFi protocols and earn fees plus token rewards.
Simply buying: Dollar-cost averaging into Bitcoin every week. Over any 4-year period in Bitcoin's history, this strategy has been profitable. No electricity bills, no hardware depreciation, no noise from ASICs.
The bottom line
Mining is a fascinating piece of how Bitcoin works, but it's no longer a hobby project. It's an industrial business that favors scale and cheap power. For most individuals, staking or just buying crypto directly makes more economic sense.
Related: What is Bitcoin?, crypto staking, crypto security.