Glossary

Gas Fee

Plain-language definition Crypto glossary

Key takeaways

A gas fee is the payment required to perform a transaction or execute a smart contract on a blockchain, compensating validators or miners for the computing resources your action consumes.
Every operation has a cost measured in units of gas, and your total fee is the gas used multiplied by the price you are willing to pay per unit, so fees rise with demand and fall when activity is light.
Gas fees determine how affordable a network is to use, and high fees during congestion are a major reason Layer 2 scaling solutions exist.

Definition

A gas fee is the payment required to perform a transaction or execute a smart contract on a blockchain. It compensates validators or miners for the computing resources your action consumes and helps prevent the network from being spammed.

How it works

Every operation has a cost measured in units of “gas.” Your total fee is the amount of gas used multiplied by the price you are willing to pay per unit. When the network is busy, users bid higher prices to have their transactions included sooner, so fees rise with demand and fall when activity is light.

Why it matters

Gas fees determine how affordable a network is to use, and high fees during congestion are a major reason Layer 2 scaling solutions exist. Understanding gas also helps you avoid overpaying or having a transaction stall because the fee was set too low.

Example

On Ethereum, gas is denominated in gwei, a tiny fraction of one ether, and wallets estimate the fee before you confirm.

FAQ

Frequently asked questions

Why do gas fees go up and down?

Your fee is the gas your action uses multiplied by the price you pay per unit of gas. When the network is busy, users bid higher prices to have their transactions included sooner, so fees rise with demand and fall when activity is light.

What are gas fees actually paying for?

Gas fees compensate the validators or miners for the computing resources your transaction or contract execution consumes. They also help prevent the network from being spammed, since every operation carries a real cost.

How can I avoid overpaying on gas?

Understanding gas helps you set a fee that is neither too high nor too low, since overpaying wastes money and underpaying can leave a transaction stalled. Transacting when the network is less congested generally means lower fees, and Layer 2 networks exist partly to reduce these costs.