Gas fees refer to the cost required to successfully conduct a transaction on a blockchain. Think of it as the "fuel" for the network—just as a car needs gasoline to move, a blockchain needs gas to process your actions.
Why do I need to pay gas fees?
Every action on the blockchain (sending tokens, swapping on a DEX, or minting an NFT) requires computational effort.
Rewarding Validators: Gas fees are paid to the validators (or miners) who use their computing power to verify your transaction and secure the network.
Preventing Spam: By attaching a cost to every action, gas fees prevent malicious actors from spamming the network with infinite, useless transactions that would slow it down for everyone.
Native Tokens: The currency of gas fees
Each blockchain has its own specific native token used to pay for gas. You must hold a balance of this token on the specific network you are currently using to perform any transaction.
Because each blockchain is a separate "road," the fuel from one network cannot be used on another. For example, if you have ETH on the Ethereum network but are trying to make a transaction on Arbitrum, your Ethereum ETH cannot pay for the Arbitrum gas—you must hold ETH specifically on the Arbitrum network.
Common native tokens include:
Ethereum: Paid in ETH
BNB Chain: Paid in BNB
Polygon: Paid in POL
Arbitrum/Optimism: Paid in ETH
If you have a wallet full of USDT but zero ETH on the Ethereum network, you will not be able to send that USDT because you cannot pay the gas fee.
Customizing Transaction Speed in Rabby
When you sign a transaction in Rabby, you can choose how much gas you want to pay. Higher fees incentivize validators to process your transaction faster. Rabby offers four presets:
Fast: Best for time-sensitive trades or high network congestion.
Normal: The recommended setting for most users.
Slow: A standard fee for non-urgent transactions.
Custom: Allows you to manually set the Gas Price.