⛏️ Mining & Proof of Work, Simply

Nobody's digging

"Mining" isn't digging anything up.

It's computers racing to solve a puzzle — and that race is what keeps Bitcoin honest.

The race

Miners compete to solve a math puzzle. There's no clever shortcut — you just guess, over and over, as fast as your hardware allows.

Whoever solves it first gets to add the next block to the chain, and earns newly issued bitcoin plus transaction fees as a reward.

Everyone else's electricity was spent for nothing.

Why it's secure

The puzzle is expensive to solve but instant to verify.

That imbalance is the whole trick. Rewriting history would mean redoing all that expensive work again — for every block after it, faster than everyone else combined.

Once enough blocks have been added, that becomes unrealistic.

Difficulty adjustment

The puzzle automatically gets harder or easier roughly every two weeks.

That keeps new blocks arriving about every 10 minutes — no matter how many miners join or leave.

Nobody schedules this. It's self-correcting.

Try it: Guess the hash

Race three rival miners. There is no skill — only trying.

Mining is not skill — it's trying, over and over, until someone gets lucky. Race three rival miners for the block reward and feel why proof of work is expensive to produce but instant to verify. Open the Guess the Hash tool →

Quick check: What does a miner earn for solving the puzzle first?

1. A share of everyone else's electricity costs
2. Newly issued bitcoin plus transaction fees ✓
3. The right to change the network rules

The block reward (new issuance, halving every ~4 years) plus the fees from the transactions they included.

Quick check: Why is proof of work considered secure?

1. It's expensive to produce but easy to verify, making history costly to rewrite ✓
2. It's encrypted so nobody can read the blocks
3. Only licensed miners are allowed to participate

Anyone can check a winning answer in an instant — but producing one costs real energy. Faking history means paying that cost again, for every block since.

Next up

Every solved puzzle becomes a block.

Let's see how those blocks connect into something nobody can quietly rewrite.