All terms
A billionth of an ETH, and the unit gas prices are quoted in.
One ETH is one billion gwei, and one gwei is one billion wei. Gas prices are quoted in gwei because whole ETH would be an absurdly large unit and wei would be an absurdly small one.
When someone says gas is at 12 gwei, they mean each unit of computation costs 12 billionths of an ETH.
A 21000 gas transfer at 12 gwei costs 0.000252 ETH.
That a low gwei number means a cheap transaction. Gwei is only the price per unit of gas. A complex transaction burns many more units than a simple transfer, so a swap at low gwei can still cost more than a send at high gwei.
Common questions
Why quote gas in gwei instead of ETH?
How do I turn a gwei price into a dollar cost?
Where to go next
More foundations terms
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