What is Total Value Locked (TVL)?

Total value locked (TVL) is a metric that measures the aggregate value of all crypto assets locked in decentralized finance (DeFi) protocols via smart contracts. It was popularized by DeFi Pulse in 2019, but with price data that goes back to DeFi's genesis in 2017. TVL can also refer to the amount locked on a specific protocol (such as Aave or Uniswap). TVL data can also be further broken down and measure the DeFi value locked by purpose or type (such as lending and derivatives).