Mining

Crypto & Digital Assets · basic · CC-BY-4.0

In the context of cryptocurrency, mining is the computational process by which new transactions are verified, grouped into blocks, and permanently recorded on a proof-of-work blockchain. Miners compete to solve a cryptographic puzzle (finding a nonce that produces a hash below a target value), and the first to succeed earns the block reward — newly minted cryptocurrency plus transaction fees — as compensation for their computational effort.

Key takeaways

Bitcoin mining uses the SHA-256 proof-of-work algorithm; miners must repeatedly hash block headers until finding a nonce that produces a hash below the current difficulty target.
Mining difficulty adjusts approximately every two weeks (2,016 blocks) to maintain the target block time of 10 minutes as global hash rate fluctuates.
The Bitcoin block reward started at 50 BTC per block and halves approximately every four years (210,000 blocks); as of 2024 the reward is 3.125 BTC, with the next halving expected in 2028.
Mining profitability depends on the BTC price, mining hardware efficiency (measured in joules/TH), electricity cost, and network difficulty — making it highly sensitive to market cycles.
Ethereum transitioned from proof-of-work mining to proof-of-stake validation ('The Merge,' September 2022), eliminating ETH mining entirely.

Explanation

Cryptocurrency mining is the mechanism by which the Bitcoin network achieves trustless consensus — the ability for a decentralized system of mutually distrusting participants to agree on the state of a shared ledger without requiring a central authority. The proof-of-work consensus mechanism, invented by Satoshi Nakamoto in the Bitcoin whitepaper (2008), solves the Byzantine Generals Problem by making the creation of valid blocks computationally expensive while making the verification of valid blocks trivially cheap.

The mining process begins when a miner collects pending transactions from the mempool (the pool of unconfirmed transactions broadcast to the network) and assembles them into a candidate block. The miner then repeatedly hashes the block header — which includes a cryptographic hash of the previous block (linking the chain), a Merkle root of all transactions, a timestamp, and a variable 'nonce' value — using the SHA-256 algorithm. The target is to find a hash value with a specified number of leading zeros; the more leading zeros required, the lower the probability of any single hash attempt succeeding, and the greater the total computational work required on average.

Mining has evolved from a hobbyist activity performable on consumer CPUs to an industrial-scale operation requiring specialized Application-Specific Integrated Circuits (ASICs) — chips engineered exclusively for SHA-256 hashing at maximum efficiency. Modern mining farms consume hundreds of megawatts of electricity, with operations concentrated in regions offering cheap power: historically China (before the 2021 mining ban), and now the United States (Texas, Kentucky), Iceland, Kazakhstan, and Canada. The environmental impact of Bitcoin mining — an estimated 100–150 TWh of annual energy consumption — has been a major point of criticism and a driver of ESG-related investment restrictions.

For investors, Bitcoin mining exposure can be accessed directly through owning mining hardware and participating in mining pools, or indirectly through shares of publicly listed mining companies such as Marathon Digital Holdings, Riot Platforms, or CleanSpark. Mining company equities tend to have high operational leverage to Bitcoin prices — as BTC rises, mining profitability and stock prices rise dramatically; as BTC falls, high fixed electricity and capex costs pressure margins severely. The 'halving cycle' — the predictable reduction in block rewards approximately every four years — is a major driver of mining economics and has historically preceded bull markets as reduced supply growth meets sustained or growing demand.

Formula

Mining Profitability = (Block Reward × BTC Price / Network Hashrate × Machine Hashrate) − Electricity Cost

Example

In early 2024, following the fourth Bitcoin halving (reducing rewards from 6.25 BTC to 3.125 BTC per block), a mining farm operating 10,000 Antminer S19 Pro units (each with 100 TH/s hash rate and 3,250W power consumption) faced a dramatically altered economics picture. At $70,000/BTC with electricity at $0.05/kWh, daily revenue per machine was approximately $12.50 (post-halving) versus $25 (pre-halving), while electricity cost per machine was approximately $3.90/day. Gross margin per machine: $8.60/day, requiring the operation to carefully manage the timing of hardware upgrades and energy procurement to remain profitable.

Mining

Key takeaways

Explanation

Formula

Example

Related terms