What Is Gwei?
Gwei is a denomination of Ether (ETH) used to express gas prices on the Ethereum network. 1 gwei = 0.000000001 ETH (10⁻⁹ ETH). When you see gas prices quoted as "30 gwei," it means each unit of gas costs 0.00000003 ETH. The name comes from "giga-wei," where wei is the smallest possible unit of ETH.
How Gwei Works
Ethereum gas prices fluctuate based on network demand. During quiet periods, gas might be 10-20 gwei. During NFT mints, DeFi rushes, or memecoin frenzies, it can spike to 200+ gwei. The cost of a standard ETH transfer at 30 gwei is approximately 21,000 gas units × 30 gwei = 630,000 gwei = 0.00063 ETH (~$1.50 at $2,400/ETH).
Why It Matters for Traders
Gwei prices directly determine DeFi transaction costs. A complex smart contract interaction (like a Uniswap swap) uses ~150,000-300,000 gas units, costing $5-30+ depending on gwei price. Timing transactions during low-gwei periods (late night/weekends) can save significant fees for active DeFi traders.
