What are Ethereum gas fees?

You need to pay ETH as gas fees when you start a transaction on Ethereum with an ETH wallet, and the gas fees can only be paid with ETH. The Ethereum network will prioritize the transactions with higher gas fees.

Learn more: What is the miner fee?

What is EIP-1559?

Ethereum Improvement Proposal (EIP) 1559 aims to change the way gas fees are estimated so as to help users save costs and effectively increase the probability of their transactions being confirmed by the Ethereum network.

Further reading:

Ethereum’s London hard fork: What is EIP-1559?

How are gas fees calculated?

Before calculating, you need to know the following 5 concepts first.

  • Gas: the Ethereum network consumes computational resources to execute each transaction, and gas is the unit of measuring resources.
  • BaseFee: the lowest price of gas calculated by the Ethernet network to ensure a successful transaction.
  • PriorityFee: the tip you pay for each unit of gas to speed up the transaction.
  • MaxPriorityFee: the maximum tip you pay for each unit of gas.
  • MaxFee: the maximum price you pay for each unit of gas

Gas Fees = Units of Gas Used * (BaseFee + PriorityFee)

You can think of the process of transferring a certain amount of tokens as driving a car, and the gasoline consumed during the journey is Gas.

The costs(i.e. the gas fees) are the gasoline consumed for the journey multiplied by the price of gasoline (baseFee + PriorityFee).

BaseFee is calculated by the Etheruem network to ensure the car arrives at the destination successfully; PriorityFee is the tip you set to speed up the car's arrival. The more the tip you pay, the faster the transfer will go through.

How to set gas fees

imToken supports two ways of setting gas fees: Set priority and Customize

Open imToken ETH wallet and tap on the token you want to make a transaction. We’ll take ETH as an example here.

Set priority

There are three transaction speeds: "Fastest" ,"Standard" and "Economy". Different speeds means different transaction confirmation times, the higher the gas fees you pay, the faster the transaction is confirmed.

Note:If you want to choose "economy", you can learn more through this article.

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Please note that imToken's estimated range of gas fees are based on the current Ethereum network conditions, with a minimum value of (BaseFee + PriorityFee) * Gas and a maximum value of MaxFee * Gas.


For advanced users, who understand the mechanism of EIP-1559, you can manually set gas fees by modifying maxFee, maxPriorityFee, and Gas through the Customize feature.

If you want to speed up the transaction, set a higher MaxPriorityFee and make sure MaxFee ≥ BaseFee + MaxPriorityFee.

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If you want to modify the Gas (which is usually not recommended, imToken will set a Gas based on the type of transaction you’re making to ensure its success), you can check the appropriate Gas of similar transactions via Etherscan, an Ethereum blockchain explorer.

For example, if you want to sell an NFT on OpenSea, you can use Etherscan to find out the Gas Used by this type of transaction. As you can see from the chart below, the Gas Used for trading 1 NFT for some Ether is around 210,000, so the Gas you set must be greater than that.



  • The gas fees are charged by the Ethereum network rather than imToken.
  • The transaction is likely to fail if the Gas is too low. The gas fees you paid to Ethereum network will not be refunded even if the transaction fails. It is recommended to set a higher Gas  to avoid losing gas fees due to failed transactions.