Bitcoin mining is the process of running specialised computers that compete to add the next block of transactions to the blockchain, earning newly created bitcoin for whoever wins. Through that one mechanism, the network gets secured and new supply gets issued. Network computing power sat near 929 exahashes per second in mid-2026, according to D-Central research.
What miners are actually doing
Guessing. At a scale that only makes sense once you see the network collectively attempting hundreds of quintillions of guesses every second. Very fast. Very expensive.
Miners take the block they want to add, combine it with a changing number called a nonce, and run the result through a hashing function. Below a target the network sets, the output has to fall. Since no shortcut exists for calculating the right nonce, machines try billions of combinations per second until one works.
Whoever finds it broadcasts the block. In a fraction of a second every other node verifies it, and that asymmetry is what makes the whole system work. Solving takes enormous effort. Checking takes almost none.
What a miner earns
Two components. The balance between them shifts over time.
Newly created bitcoin makes up the block reward, currently 3.125 BTC per block following the April 2024 halving. That cut daily issuance from 900 BTC to 450 BTC.
Paid by users competing for space in the block, transaction fees make up the rest. Most of the time they are a minority of miner income, spiking during congestion.
Each halving cuts the subsidy while leaving fees untouched, so fees become a progressively larger share of what pays for network security. Around April 2028 the next one arrives.
The hardware
| Era | Equipment | Status |
|---|---|---|
| 2009 to 2010 | Ordinary CPUs | Obsolete |
| 2010 to 2011 | Graphics cards (GPUs) | Obsolete for Bitcoin |
| 2011 to 2013 | FPGAs | Obsolete |
| 2013 onward | ASICs, built for SHA-256 only | Current |
Efficiency is the competitive variable, measured in joules per terahash. At 15 J/TH runs the Bitmain Antminer S21 Pro. Hydro-cooled S23-class hardware reaches roughly 9.5 J/TH, close to half the energy draw of a four-year-old S19 Pro for the same work.
Home mining Bitcoin profitably ended over a decade ago. Economics now favour operators with cheap electricity at industrial scale.
Difficulty adjustment
Regardless of how much computing power is pointed at it, Bitcoin targets one block roughly every ten minutes.
Every 2,016 blocks, about two weeks, the network measures how fast those blocks arrived and adjusts the target. With more miners joining, the puzzle gets harder. With miners leaving, easier.
In February 2026, difficulty reached 144.4 trillion after a 15% single-adjustment jump, the largest since China's 2021 mining ban. By mid-year it eased to around 124.9 trillion as weaker operators powered down.
Mining pools and the centralisation problem
Solo mining a block is effectively a lottery ticket, since a single machine's odds of finding the winning hash before the rest of the network does are vanishingly small at current difficulty levels. Combining hashrate and sharing rewards proportionally, pools solve that.
Concentration is the result, and the open structural risk in Bitcoin mining. Per D-Central, the Nakamoto coefficient sat at 3 in mid-2026, meaning only three pools were needed to exceed half of all blocks produced. Foundry USA alone held roughly 27%.
One qualification matters. Pool concentration is not ownership concentration. At any time, individual miners can redirect hashrate to a competitor while retaining full control of their hardware. What pools control is transaction selection, not the machines.
That distinction is why Stratum V2 matters. In May 2026, seven of the largest pools, representing nearly 75% of global hashrate, agreed to adopt the protocol. Under it, individual miners choose which transactions go into blocks rather than leaving that to the pool operator.
Energy, honestly
By design, mining consumes real electricity, since the expense is what makes attacks uneconomic.
In its 2025 study, the Cambridge Centre for Alternative Finance reported a 52.4% sustainable energy mix, comprising 42.6% renewables and 9.8% nuclear. Geographic distribution has shifted repeatedly, with the United States accounting for 37.4% of hashrate and Russia 16.9% following legalisation.
Two points get lost in most coverage. Tracking hashrate and reward value rather than transaction count, energy use makes the widely quoted "energy per transaction" figure meaningless. And miners chase the cheapest power available, which frequently means stranded or surplus generation with no other buyer.
Why mining is a difficult business
- Margins compress after every halving. Revenue halves overnight while costs do not.
- Hashprice determines survival. Miner revenue per petahash per day fell to between $28 and $30 in Q1 2026, among the lowest readings on record.
- A large share operate underwater. CoinShares estimated up to 20% of miners were unprofitable in May 2026.
- Hardware depreciates fast. Each ASIC generation makes the last less competitive.
- Revenue is denominated in a volatile asset while electricity bills are not.
Where mb.io fits
Mining is one way to acquire bitcoin. Buying it on a regulated exchange is the other, needing no hardware, no electricity contract, and no exposure to hashprice.
mb.io is a regulated crypto spot exchange backed by MultiBank Group, a financial institution founded in 2005 that serves more than 2 million clients across 100+ countries.
- Regulated by VARA in the UAE and AUSTRAC in Australia
- 10/10 security score from Hacken, an independent blockchain security auditor
- Institutional-grade MPC custody powered by Fireblocks, with segregated client funds
- A curated list of assets, so you're not sorting through thousands of tokens to find the ones worth trading
- Buy, sell, and swap in three steps, from sign-up to purchase
- 24/7 multilingual client support
Open your account and start trading on mb.io.
Frequently asked questions
How does Bitcoin mining actually work?
Machines guess random numbers until one produces a hash below the network's target. The winner adds the next block and receives newly created bitcoin plus the transaction fees inside it.
How much does a miner earn per block?
3.125 BTC in newly issued coins following the April 2024 halving, plus the transaction fees in that block. The subsidy halves again around April 2028, dropping to 1.5625 BTC.
Can I still mine Bitcoin at home?
Not profitably in any normal case. Bitcoin mining requires ASIC hardware and industrial-scale cheap electricity, and CoinShares estimated up to 20% of professional miners were operating unprofitably in May 2026.
What is hashrate?
The total computing power securing the network, measured in hashes per second. Bitcoin crossed one zettahash per second in late 2025 and sat near 929 exahashes per second by mid-2026.
Why does mining difficulty change?
To keep block times near ten minutes. Every 2,016 blocks the network recalculates the target, making the puzzle harder when hashrate rises and easier when it falls.
Is Bitcoin mining bad for the environment?
It consumes substantial electricity by design, since that cost is the security mechanism. Cambridge Centre for Alternative Finance data put the sustainable share at 52.4% in its 2025 study.
What is a mining pool?
A group combining hashrate and sharing rewards proportionally, which converts an unpredictable lottery into steady income. Concentration is the trade-off, with three pools producing over half of all blocks in mid-2026.
Do other cryptocurrencies use mining?
Some do, including Litecoin, Dogecoin, and Monero, all of which use Proof of Work. Ethereum moved to Proof of Stake in September 2022 and no longer has miners.
