Gas fees are transaction fees paid on a blockchain to reward validators (miners or stakers) who execute your transfer or smart contract interaction. The term "gas" comes from Ethereum, by analogy with the fuel powering the network's computers.
How it works on Ethereum:
- Each operation has a cost in gas units: a simple ETH transfer = 21,000 gas, a Uniswap swap = ~150,000 gas, an NFT mint = 200,000-1,000,000 gas
- You pay a price per gas (gwei = nano-ETH) that fluctuates with network congestion
- Total fee = gas units × gas price
Typical Ethereum L1 gas levels:
- Quiet network (night, weekend): 10-20 gwei → swap = $1-3
- Active network (Europe/US hours): 30-60 gwei → swap = $5-15
- Hype (NFT mint, airdrop, DeFi crash): 200-500+ gwei → swap = $50-200
- Historical records (May 2021, Yuga Labs Otherside): >2000 gwei → transactions at $5,000+ for hours
EIP-1559 (August 2021) redesigned Ethereum's gas system:
- Base fee: automatically adjusted by the protocol, burned (reduces ETH money supply)
- Priority fee (tip): optional tip to be processed faster
Solutions to reduce fees:
- Layer 2 (Arbitrum, Base, Optimism): 10-100× cheaper than Ethereum L1 thanks to transaction batching
- Solana, Avalanche, BSC: Ethereum alternatives with sub-$0.01 fees
- Bitcoin Lightning Network: near-instant and free BTC transactions
- Schedule transactions during low-congestion hours (US nights, Sundays)