EtherScore is a decentralized, on-chain reputation system for users and dApps on blockchains. It certifies the on-chain reputations of Ethereum users based on their previous actions (transaction history). User activity is represented by NFTs, which reflect the concept of collectible badges. Anyone can issue badges to identify and target specific users based on one or more minting conditions (e.g. "having done 10 swaps on Uniswap") without coding.