Classroom search

Proof of work is a hunt for a hash that meets a target. The picture is decoration. The game below uses the same words: nonce, hash, zeros.

How the mini-game works

Proof of work is easier once you have pressed a button. BitBuddy’s mining game is a tiny version of the search real miners do. Toy SHA-256. Not a real miner. No coins.

  1. A block needs a special hash (it must start with enough zeros).
  2. Type any nonce (a number) and click Mine.
  3. If the hash does not qualify, try another nonce — that search is the “work.”

In Bitcoin, miners change the nonce until SHA-256(block header) meets the network target. You’re doing a tiny version of that search. No real coins.

Words you will see

  • Nonce — the number you change each try.
  • Hash (SHA-256) — a fingerprint of the block header + nonce.
  • Target — the hash must start with N zeros.
  • Block header — the data being hashed (previous hash + time + nonce).

What problem the work is solving

A public ledger needs a way to decide who writes the next page, and to make rewriting old pages expensive. Proof of work does that by turning “I propose this block” into “I found a nonce that makes the header hash meet the target.” Anyone can check the hash quickly. Finding it takes many tries.

Real miners group transfers into a block and search for a nonce that makes the hash meet a network rule. The first valid result can add the block. That search uses real electricity. Pools exist because solo searchers rarely win. None of that happens on this website.

Bitcoin also pays a block reward plus transaction fees to the miner who finds a valid block. That is how new coins enter circulation and how some fees are collected. It is not a salary BitBuddy can send you, and it is not a reason to buy hardware after one lesson.

Difficulty is a classroom slider here

In the game you pick how many leading zeros the hash must have. More zeros means more expected tries. That is enough to feel why “work” is a search and not a clever password. On Bitcoin, difficulty adjusts so that blocks arrive on a roughly steady schedule as machines join or leave. We are not simulating that control loop, and we are not scoring your electricity bill.

If two people find a valid hash at once, the network eventually picks one chain to extend. The game does not show that race. One browser, one toy header, one target.

What it represents — and what it does not

This site only paper-trades and runs a tiny hash search. Nothing here mines a live block or pays coins. Difficulty in the game is a classroom slider (how many leading zeros). On Bitcoin, difficulty adjusts so blocks arrive on a roughly steady schedule as machines join or leave. We are not simulating that adjustment.

If you want the picture of how blocks attach, open the teaching chain first, then come back and play.

Play the mini-game

Same words as above. Start with nonce 0 and press Mine.

Start the mining game

After the game

You now have the vocabulary for work, hash, and target. The path turns to risk and scams — the trust lesson that belongs before anyone talks about a real exchange — then paper trading and fees.

Key takeaways

  • Proof of work is a search: change a nonce until the hash meets a target.
  • Real mining uses real electricity. This site runs a toy SHA-256 search.
  • A block reward plus fees is how Bitcoin pays miners — not a classroom payout.
  • The mining game uses the same words: nonce, hash, target. No coins.

Check-in · not a grade

Quick check-in

A short pass over nonce, hash, and what this game is not. No timer. No score that follows you off this site.

  1. What is a nonce in this lesson?
  2. Proof of work is mainly:
  3. BitBuddy’s mining game:
  4. On Bitcoin, a miner who finds a valid block is paid:
  5. In the game, asking for more leading zeros:

Continue the path

Feel the search

Change a nonce until the hash meets a target. Toy SHA-256. No coins.

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