Government-issued currency not backed by a physical commodity (e.g., USD, EUR, JPY).
Fiat currency is government-issued money that derives its value from the authority and credit of the issuing government rather than from a physical commodity like gold. The word 'fiat' comes from Latin meaning 'let it be done' — essentially, money by decree. All major world currencies today are fiat: the US Dollar, Euro, Japanese Yen, and British Pound. Fiat currencies are controlled by central banks that can adjust monetary supply through interest rates, quantitative easing, and money printing. Bitcoin was explicitly created as an alternative to fiat — its whitepaper cites the problems of trust-based fiat systems. In crypto, 'fiat on-ramp' refers to services that let you buy crypto with traditional currency, while 'fiat off-ramp' means converting crypto back to government currency.
Fiat currency is government-issued money (USD, EUR, GBP, JPY) that derives its value from government decree rather than being backed by a physical commodity like gold. The term is used extensively in crypto to distinguish between traditional currencies and cryptocurrencies. Fiat 'on-ramps' and 'off-ramps' describe the process of converting between fiat and crypto — typically through centralized exchanges (Coinbase, Binance), peer-to-peer platforms, or crypto ATMs. The efficiency and cost of fiat on/off-ramps varies dramatically by country: US and European users have relatively seamless options, while many developing nations face limited exchange access, high fees, and regulatory restrictions. Stablecoins (USDT, USDC, DAI) bridge the gap by representing fiat value on-chain, enabling fiat-like transactions without leaving the blockchain ecosystem.
When the Federal Reserve printed trillions of dollars during COVID-19 stimulus programs (2020-2021), it exemplified why Bitcoin advocates see fiat's unlimited supply as a fundamental flaw compared to Bitcoin's fixed 21 million cap.
The term distinguishes government money from cryptocurrency. 'Fiat' comes from Latin meaning 'let it be done' — reflecting that fiat currency has value because the government says so, not because it's backed by something physical. In crypto discussions, it's a neutral technical term, though some use it with skepticism about government monetary policy.