Bitcoin (BTC)

Layer 1 blockchain · Store of value

Bitcoin is the first cryptocurrency, launched in January 2009. It runs on a proof-of-work network with a fixed limit of 21 million coins, and most people hold it as a long-term, scarce digital asset.

Profile last verified 23 September 2026. Live figures from CoinGecko. Not investment advice.

Bitcoin price chart

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What is Bitcoin?

Bitcoin was described in a 2008 white paper by the pseudonymous Satoshi Nakamoto and went live on 3 January 2009. It lets people send value directly to each other without a bank, with transactions recorded on a public ledger that anyone can verify.

New bitcoins are created as a reward for miners, who compete to add blocks roughly every 10 minutes. The reward halves about every four years; the April 2024 halving cut it to 3.125 BTC per block. About 95% of all bitcoin that will ever exist has already been mined.

Key facts

TickerBTC
TypeLayer 1 blockchain · Store of value
LaunchedJanuary 2009
ConsensusProof of work (SHA-256 mining)
SupplyHard cap of 21 million BTC; new issuance halves roughly every four years (next expected around 2028).
Official sitebitcoin.org

What BTC is used for

  • Long-term savings and a hedge against currency debasement (its main use today)
  • Borderless payments and remittances, including via the Lightning Network
  • Collateral and reserve asset for companies, funds and spot ETFs

Main risks

  • Large price swings: drawdowns of 70% or more have happened several times
  • Lost keys mean lost coins; there is no password reset
  • Regulation and tax rules vary by country and keep changing
  • Mining uses a lot of energy, which draws political pressure

Related guides

Bitcoin: frequently asked questions

How many bitcoins will ever exist?
At most 21 million. The limit is enforced by the software every node runs, and the issuance schedule means the last fractions will be mined around the year 2140.
What is the Bitcoin halving?
Every 210,000 blocks (about four years) the reward for mining a block is cut in half. The most recent halving, in April 2024, reduced it from 6.25 to 3.125 BTC.
Do I have to buy a whole bitcoin?
No. One bitcoin divides into 100 million units called satoshis, and most exchanges let you buy a few dollars’ worth.
Where should I keep bitcoin?
Small amounts can stay on a reputable exchange, but for larger or long-term holdings many people use a self-custody wallet, ideally a hardware wallet, and keep the recovery phrase offline.

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