You are competing to mine blocks and earn as much BTC as possible. Mining means finding a special input (called a Nonce) that makes a hash meet a specific condition. The Hash Calculator on the left is your main tool.
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The winning condition: look at the last character of your Computed Hash. It must match the difficulty condition shown by Satoshi (e.g. if difficulty is "Ended in 9", the last character must be 9). Keep changing the Nonce and clicking Calculate Hash until it does.
⛏️ Step 1 — Fill in the Hash Calculator
Look at Satoshi's screen for the current block info. Fill in all five fields:
| Previous Block Hash | Copy from your Log table on the right — use the last completed block's hash. For Block 1, use the Genesis hash. |
| Current Block Name | The block being mined right now (e.g. B1, B2…). Shown on Satoshi's screen. |
| Your Miner ID | Your assigned ID (e.g. Miner1). Always the same — never change it. |
| Transactions | The IDs of the transactions you chose, joined together with no spaces, in ascending order (e.g. T1T3T7 — always lowest number first, never T7T3T1). Choose from Satoshi's Transaction Pool. Order matters: the wrong order produces a different hash. |
| Nonce | Your guess — type any text or number. This is what you change repeatedly to find a valid hash. |
🎯 Step 2 — Find a valid hash
- 1Click Calculate Hash. Look at the last character of the result.
- 2If it doesn't meet the difficulty condition → change the Nonce (try anything: a word, a number, random letters) and click again.
- 3Repeat until the last character matches. Every change gives a completely different hash — that unpredictability is the whole point of Proof of Work.
- 4When you find a valid hash → shout "BITCOIN!" loud and clear.
📢 Step 3 — After shouting "BITCOIN!"
- 5Tell Satoshi your Nonce and your selected transactions in ascending order (e.g. "T1, T3, T7" — lowest number first). Satoshi will enter both on the main screen so everyone can verify.
- 6All other miners must enter your exact inputs in their own calculator and confirm the hash matches. This is consensus.
- 7If consensus is reached, Satoshi closes the block. You receive the block reward + all transaction fees from the transactions you included.
- 8Save the agreed hash in your Log table (right panel). You will need it as the "Previous Block Hash" for the next block — this is what makes the chain.
👁️ If someone else shouts "BITCOIN!" first
- AStop mining immediately. Enter the winning miner's exact inputs in your calculator (Satoshi will display them).
- BClick Calculate Hash. If your result matches what Satoshi shows → the block is valid. Agree.
- CIf it does not match, or any balance goes negative, or block size is exceeded → do not agree. Satoshi will reject the block and mining resumes.
⚠️ Transactions must follow two rules: (1) the total size of your chosen transactions must not exceed the Max Block Size shown by Satoshi, and (2) no player's balance can go below zero. The Satoshi screen will warn if either rule is broken.
💰 Strategy tips — how to maximise your BTC
- Pick high-fee transactions — fees go directly into your pocket when you mine the block.
- Include transactions where you receive BTC — your balance goes up even if you don't mine the block.
- Avoid transactions where you send BTC — they reduce your balance.
- Watch other miners' balances — sometimes it's worth including a transaction that hurts a rival ahead of you in the standings.