Gas Cost in USD Calculator
Gas fees are quoted in gwei, but you usually want to know the cost in dollars. This calculator takes the gas units a transaction uses, the gas price in gwei, and the current ETH price, then returns the fee in both ETH and US dollars. Use it to decide whether a swap, mint, or transfer is worth sending at the current gas price.
Gas cost formula
Fee in gwei = gas units * gas price
Fee in ETH = fee in gwei / 1,000,000,000
Fee in USD = fee in ETH * ETH price
One gwei is one billionth of an ether, so the gwei total is divided by one billion to get ETH, then multiplied by the dollar price of ETH.
Reading the result
- The ETH fee is independent of the dollar price; only gas units and gas price set it.
- The USD fee scales directly with the ETH price you enter.
- A standard transfer is 21,000 gas; contract calls cost more.
- Recheck at the moment of sending: gas price and ETH price both move quickly.
Gas cost in USD: frequently asked questions
How do I convert a gas fee to dollars?
Multiply the gas units by the gas price in gwei to get the fee in gwei, divide by one billion to get ETH, then multiply by the ETH price in dollars. This calculator does all three steps and shows the fee in both ETH and USD.
How many gas units does a transaction use?
A simple ETH transfer uses 21,000 gas units. Token transfers, swaps, and other smart-contract interactions use more, often from tens of thousands to several hundred thousand gas units depending on the contract. Enter the gas estimate your wallet shows for the specific transaction.
What gas price should I enter?
Use the current gas price in gwei, which you can read from your wallet or a network gas tracker. Under EIP-1559 this is the effective per-gas fee, the base fee plus your priority tip. Gas prices change continuously with network demand, so use a live value.
Why does the dollar cost change so much?
Two moving parts drive it: the gas price in gwei, which rises when the network is congested, and the ETH price in dollars. A transaction can cost a few cents when the network is quiet and several dollars during peak demand, even for the same gas units.
Sources and method
- The conversion is the standard gas-cost identity: gas units times gas price in gwei, converted to ETH and then to USD. All inputs are user-editable; no price is hardcoded.
- Ethereum Foundation: Gas and fees documentation.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.