What is a gas fee?
Every action on Ethereum burns a little computing effort. Gas is how that effort is measured — and priced.
On this page
A gas fee is the charge for processing a transaction on Ethereum and similar networks. Gas measures the computing work a transaction needs; the fee is the gas used multiplied by a per-unit price made up of a base fee, which is burned, and an optional tip to the validator.
How is a gas fee calculated?
Ethereum's developer docs define gas as the unit for the computational effort needed to run operations on the network. Prices are quoted in gwei, one-billionth of an ETH. The formula is: fee = gas used × (base fee + priority fee). A simple ETH transfer needs a gas limit of 21,000 units; interacting with a smart contract usually needs more.
What do base fee, priority fee and max fee mean?
| Term | Meaning |
|---|---|
| Gas limit | The most gas you allow the transaction to use |
| Base fee | A per-gas price set by the protocol from previous blocks, moving by at most 12.5% per block; it is burned, removing that ETH from circulation |
| Priority fee (tip) | An extra per-gas amount paid to the validator to include you |
| Max fee | The highest per-gas price you will pay; the difference above base fee plus tip is refunded |
This structure arrived with EIP-1559 in the London upgrade of August 2021, according to ethereum.org's fork history. While a transaction waits to be picked up it sits in the mempool, and you can check the fee you actually paid on a block explorer.
Why do failed transactions still cost gas?
Because the network still did the work. The docs explain that if a transaction runs out of gas, its changes are reverted but the gas it consumed is still charged. Setting a gas limit too low therefore costs money and achieves nothing. Fees also vary over time, and layer-2 networks are one way to pay less — compare them in layer 1 vs layer 2 and Ethereum rollups explained.
Questions readers ask
Who receives the gas fee?
On Ethereum, the base-fee part is burned and the priority fee goes to the validator that includes your transaction.
Is gas paid in a separate token?
No. Gas is a unit of work, priced in gwei, and paid in ETH on Ethereum. You need some ETH in your wallet even to move other tokens.
A gas fee is computing work multiplied by a price per unit. Keep a little ETH for fees, leave sensible headroom in the gas limit, and check the fee you actually paid on an explorer. For the network itself, read what is Ethereum.
Sources
- ethereum.org, Gas and fees (developer documentation) (2026)Primary source
- ethereum.org, History of Ethereum forks (2026)Primary source
Educational content only — not financial, investment, legal or tax advice. Crypto-assets are high-risk and you could lose all the money you put in. Rules differ by country; check with your national regulator. See our risk disclosure and editorial policy.
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