Gas and swap cost estimator
Enter the gas a transaction uses, the gas price in gwei and the price of the chain's native token to estimate the network fee. Add a swap size to include Rabby's swap fee and compare it with a 0.875% fee. You type every value, so nothing is fetched or sent.
How the estimate works
Network fee = gas units × gas price (in gwei) × 0.000000001 × native token price. Rabby shows the real gas estimate and fee on its confirmation screen before you sign; use those numbers when you have them. Gas used varies with the token and the contract, so the presets are typical values, not exact ones.
On layer-2 networks such as Arbitrum, Base and Optimism, gas prices are usually a small fraction of Ethereum mainnet's, so the same transaction can cost cents instead of dollars. The default swap fee of 0.25% and the 0.875% comparison are explained in Rabby swap fees.
Frequently asked questions
Where do I find the current gas price?
Rabby's confirmation screen shows the gas price and the estimated fee for the network you are using, and lets you choose a slower or faster setting.
Why did my swap cost more than the estimate?
Complex routes use more gas, and the price you receive also depends on slippage and routing, which is separate from any fee.
Can I pay gas without holding ETH?
Rabby's Gas Account lets you pay gas on supported chains from a stablecoin balance. See our Gas Account guide.