Gas Fees
Web3 / blockchain technology
The fee paid to validators or miners for processing and including a transaction in a block on transaction-fee-based blockchains—most prominently Ethereum, where fees are denominated in 'gas' units measuring computational complexity. Gas fees on Ethereum consist of a base fee (burned since EIP-1559) that automatically adjusts to network congestion, plus an optional priority fee (tip) paid to validators for faster inclusion. High gas fees during network congestion (DeFi summer 2020, NFT bull market 2021-2022) regularly priced out retail users from DeFi, driving adoption of L2s that process transactions off-chain and batch them to Ethereum. Ethereum L2s including Arbitrum, Optimism, and Base reduced gas costs by 10-100x, while the Dencun upgrade (March 2024) introducing blob transactions reduced L2 fees by another 10-20x, bringing typical L2 transactions to fractions of a cent. Example: During peak DeFi activity in May 2021, swapping on Uniswap on Ethereum mainnet cost $100-300 in gas fees. The same swap on Arbitrum after the Dencun upgrade costs $0.01-0.05, making small DeFi transactions economically viable for the first time. Why it matters for Web3: Gas fees are the primary UX and economic barrier to mass DeFi and blockchain adoption. The trajectory of L2 fee reduction is the most important infrastructure trend determining which user segments can practically access decentralized applications.
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