Gwei

Gwei(giga-Wei, sometimes called “Shannon”) is the unit Ethereum gas prices are quoted in. One Gwei equals 10⁻⁹ ETH = 10⁹ Wei. A typical gas price of 25 Gwei is therefore 0.000000025 ETH per unit of gas.

Why Gwei specifically? Two reasons. Gas prices in raw Wei would be inconveniently large numbers (10¹⁰ - 10¹¹ Wei per unit gas at typical rates), and gas prices in ETH would be inconveniently small (10⁻⁸ ETH). Gwei lands in the human-readable middle: single- to triple-digit decimal numbers that fit on a wallet screen without scientific notation.

On EIP-1559 transactions (post-London hard fork, August 2021) the gas price decomposes into base fee (set algorithmically, burned) and priority fee (tip to validators). Both are denominated in Gwei.

Convert any value between the three Ethereum denominations with our Wei / Gwei / ETH converter, which uses BigInt math so even values larger than JavaScript’s 15-digit Number precision round-trip exactly.