Gwei to ETH Converter

Your wallet quotes gas in gwei (12, 0.8, 45) and then charges you in ETH. With 1 ETH equal to 1,000,000,000 gwei, counting zeros by hand is exactly how people end up off by a decimal place and panic over a fee that is a thousand times smaller than it looks. Type the number, pick the direction, and the equivalent shows up right away, with nine decimal places on the ETH side.

The math is just a nine zero shift, but the display has a catch. Going from gwei to ETH, the output is cut at nine decimals, which is exactly the size of one gwei. Any gas price under 1 gwei, normal on L2s and during quiet hours, comes out as 0.000000000. The way around it is to convert the total cost instead of the unit price: 0.3 gwei times 21,000 gas is 6,300 gwei, and that number converts cleanly.

To get an actual fee you need two things this page never asks for: the gas used (21,000 for a plain ETH transfer, far more for a swap or a mint) and the price per unit in gwei. Multiply them, drop the total in here, and you have the cost in ETH. There is no price feed built in, so converting to dollars is a separate step. Nothing leaves the page; the math runs in your browser.