Crypto & Digital MoneyBitcoin Supply

Why Only 21 Million

A money supply fixed in code

More dollars appear every year. Bitcoin's code caps its coins at 21 million. So when does the very last one arrive?

You'll find out

  • The line written in bitcoin's code
  • How much already exists
  • The year the last coin appears

Why it matters

A supply fixed in code works nothing like the dollars in your account. Seeing how it works ends the hype and the fear.

About 3 min6 interactive slides · 5 questionsLesson 121 · Zone 14

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More in this zone

  1. 118CryptocurrencyMoney Without a BankBitcoin moves value with no one in the middle
  2. 119BlockchainThe Shared NotebookA blockchain is a record everyone keeps a copy of
  3. 120Crypto HistoryNobody Knows Who Made BitcoinIts creator vanished and left a fortune untouched
  4. 122Crypto SecurityKeys and WalletsWhoever holds the key holds the coins
  5. 123HindsightThe 10,000-Bitcoin PizzaIn 2010 a programmer bought two pizzas with coins later worth hundreds of millions
  6. 124Crypto PrivacyCrypto Is AnonymousEvery bitcoin payment is public forever
  7. 125HerdingFear of Missing OutWatching others get rich makes us forget the risks
  8. 126Crypto HistoryThe Coin That Started as a JokeDogecoin was created to make fun of crypto