Wei

Wei is the smallest divisible unit of Ethereum, with one Ether equaling exactly 1,000,000,000,000,000,000 Wei (10^18). Named in honor of Wei Dai, the cryptographer and computer engineer who pioneered b-money, an early theoretical precursor to Bitcoin and modern cryptocurrencies, Wei serves as Ethereum's base denomination for all on-chain transactions and smart contract operations. Just as traditional currencies use cents or satoshis, the Wei enables precise fractional transactions and gas fee calculations in Ethereum's ecosystem. Example: When a user sends 0.5 ETH to another address, the transaction actually processes 500,000,000,000,000,000 Wei at the protocol level, though the wallet interface typically displays it in more readable Ether denominations. Why it matters for cryptocurrency: Understanding Wei is fundamental for developers, traders, and users interacting with Ethereum. Gas fees, smart contract values, and precise accounting all operate at the Wei level, making it essential knowledge for accurate transaction management and avoiding costly mistakes in DeFi interactions.

Category: cryptocurrency types

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