Key Takeaways
Quick answer
A gas fee is what you pay the Ethereum network to process a transaction or run a smart contract. It is paid in ether (ETH) and equals the gas used multiplied by the base fee plus an optional tip. It rises when the network is busy.
- A gas fee pays the Ethereum network to process a transaction and is priced in gwei.
- The fee equals gas used multiplied by the base fee plus a tip, and the base fee moves with demand.
- Failed transactions still pay gas, and platform fees are charged separately.
What is gas on Ethereum?
The documentation at ethereum.org, run by the Ethereum Foundation, describes gas as the unit that measures how much computing work an operation needs. Sending ETH, swapping a token or calling a smart contract each burns through some gas. You pay for it in ETH, usually quoted in gwei, a tiny unit worth 0.000000001 ETH.
New to the network itself? Start with what Ethereum is.
How is a gas fee calculated?
ethereum.org gives the formula as “units of gas used * (base fee + priority fee)”. The base fee is burned, meaning it is destroyed rather than paid to anyone. The priority fee is a tip paid to whichever validator adds your transaction to a block.
| Simple ETH transfer | Working | Fee |
|---|---|---|
| ethereum.org example | 21,000 × (10 + 2) gwei | 0.000252 ETH |
| Busier network (illustrative) | 21,000 × (40 + 2) gwei | 0.000882 ETH |
The second row is our own arithmetic with an assumed 40 gwei base fee. The same transfer costs 3.5 times as much simply because demand was higher.
Why do gas fees go up and down?
The base fee adjusts automatically. According to ethereum.org it “will increase or decrease by a maximum of 12.5% per block”, depending on whether recent blocks were fuller or emptier than the target. When many people compete for space, users also raise their tips to get ahead.
Bitcoin has a separate system. Bitcoin.org explains that a Bitcoin fee is set by how many bytes the transaction takes up, regardless of how much bitcoin moves.
What are the common gas fee mistakes?
- Expecting a refund on failure. ethereum.org is blunt: “The fee is paid regardless of whether a transaction succeeds or fails.”
- Confusing it with a platform fee. Gas goes to the network. A trading platform’s own charges come on top; see crypto trading fees.
- Setting no ceiling. Wallets let you set a maximum fee; ethereum.org says any unused amount above the actual cost is returned.
Frequently asked questions
Do I get my gas fee back if a transaction fails?
No. The work was still done by the network, so the gas used is charged whether or not the transaction succeeds.
Who receives the gas fee?
Only the tip reaches the validator. The base fee is burned, which removes that ETH from circulation.
Article Sources
2 sources
Blockhorizon checks every figure, date and quotation against primary sources: regulators, statistics bodies and original technical documents. Read our editorial policy.
- ethereum.org, Gas and fees (updated Jun 2026) — ethereum.org (accessed 2026-10-02)
- Bitcoin.org, Frequently Asked Questions — bitcoin.org (accessed 2026-10-02)