How Mining Works

Proof of Work: Converting electricity into unforgeable security

Live Hash Attempts (Simulated)

0000000000000000000

Looking for a hash starting with many zeros...

What is Mining?

Mining is the process of adding new blocks to the Bitcoin blockchain. It serves three critical functions:

1

Transaction Processing

Miners include transactions in blocks, confirming them on the blockchain.

2

New Bitcoin Issuance

The block reward creates new bitcoin and distributes it to miners.

3

Network Security

The energy spent mining makes it prohibitively expensive to attack the network.

The Mining Process

1

Collect Transactions

Miners gather unconfirmed transactions from the mempool into a candidate block.

2

Build the Block Header

Combine the previous block hash, merkle root of transactions, timestamp, difficulty target, and a random nonce.

3

Hash the Header

Apply SHA-256 twice to the block header. This produces a 256-bit hash.

4

Check the Result

If the hash is below the difficulty target (starts with enough zeros), the block is valid. If not, change the nonce and try again.

5

Broadcast the Block

The winning miner broadcasts the new block. Other nodes verify and add it to their chain. The miner receives the block reward.

Difficulty Adjustment

Every 2,016 blocks (~2 weeks), Bitcoin automatically adjusts the difficulty target to maintain a 10-minute average block time.

Target Block Time

10 min

Adjustment Period

2,016 blocks

If blocks are found too quickly, difficulty increases. If too slowly, difficulty decreases. This ensures consistent block production regardless of how much hashpower joins or leaves.

Why Proof of Work?

Proof of Work is the only known mechanism that provides:

Unforgeable Costliness

Real energy expenditure that cannot be faked or recycled

Easy Verification

Anyone can verify a proof instantly without trusting the miner

Decentralization

No permission needed to start mining and earning rewards