Bitcoin
THERE IS A FIXED SUPPLY OF 21 MILLION BITCOIN
In brief
Like many other cryptocurrencies, Bitcoin (BTC) was designed around the principle of a finite supply. That means there’s a fixed upper limit on how many Bitcoin can ever come into existence.
In Bitcoin’s case, the upper limit was set by its creator, Satoshi Nakamoto, at exactly 21 million. For other cryptocurrencies, this cap can vary considerably—ranging from as low as 18.9 million for Monero (XMR) and Dash to as high as 100 billion for the likes of XRP and Tron (TRX).
By limiting its maximum supply, and slowing the rate at which new Bitcoin come into existence, Satoshi intended each individual Bitcoin unit (known as a satoshi) to appreciate in value over time.
According to an email purportedly shared between Nakamoto and Bitcoin Core contributor Mike Hearn, Satoshi reasoned that if 21 million coins were to be used by some fraction of the world economy, 0.001 BTC (1 mBTC) could be worth around €1. This prediction came true back in 2013, when Bitcoin first broke through the €1,000 price point; today, each mBTC is currently worth closer to €8.25.