What is a gas fee, and why is most of it destroyed rather than paid to anyone?
Gas measures computational effort, not money. Since EIP-1559 the fee splits in two, and the larger part, the base fee, is burned out of existence rather than handed to a validator.
Published · 8 min read
A gas fee is what you pay to have a transaction processed on Ethereum. The part most explanations skip is that gas is not money. Ethereum's documentation defines it precisely: gas refers to the unit that measures the amount of computational effort required to execute specific operations.
So gas is a measure of work. The fee is that measure multiplied by a price. Separating the two is what makes everything else make sense.
The two numbers in every fee
Before EIP-1559 you named a gas price and hoped. Now the fee has a fixed component and a chosen one.
The base fee is set by the protocol. You do not bid it and a validator cannot waive it. It is calculated from how full the previous block was relative to its target, and it can rise or fall by up to 12.5 per cent from one block to the next. That cap is why fees ramp rather than spike instantly, and why a busy period shows up as a steady climb.
The priority fee, usually called the tip, is what you add on top to make inclusion more attractive. This is the part you actually control and the part that competes.
There is a third number in your wallet: the max fee, or maxFeePerGas. It is the ceiling you are willing to pay. Ethereum's documentation states that the max fee must exceed the sum of the base fee and the tip, and that any unused difference is refunded. So setting a generous max fee does not mean paying it.
Where the money goes, and this is the surprising part
“The base fee is destroyed when the block is created, which removes it from circulation.”
The base fee is burned. Not paid to a validator, not paid to a foundation, not held in a treasury. Destroyed.
The validator keeps the tip and nothing else. Under normal conditions the tip is the smaller of the two numbers, which means most of what you pay in a gas fee goes to nobody at all.
That design has a purpose. If validators received the base fee, they would have an incentive to keep blocks artificially full to push it up. Burning it removes the incentive: a validator gains nothing from a higher base fee, so the only thing worth competing for is the tip.
Why a transfer is cheap and a swap is not
Because gas measures work, and the two are not the same amount of work.
Moving ETH from one address to another is a fixed, trivial operation: 21,000 units, always. A token swap runs contract code, reads and writes storage, and may touch several contracts on the way. Each of those operations has its own gas cost, and they add up.
This is why the same wallet can show a few cents for one action and a great deal more for another at the identical gas price. The price per unit did not change. The number of units did.
Gas limit and gas price are different settings
This trips people up constantly, because wallets present them side by side and the names sound related.
The gas limit is the maximum number of units of work you authorise. It is a cap on how much computation you will pay for. The gas price, now split into base fee and tip, is what each unit costs.
Raising the limit does not make a transaction faster, and it does not usually make it more expensive either, because you pay for gas actually consumed rather than for the limit. Raising the tip is what makes it faster. Setting the limit too low is what makes it fail, and a failed transaction still costs you the work it did before running out.
Gwei, and why nobody quotes fees in ETH
Gas prices are quoted in gwei because ETH is too large a unit to be readable here. One gwei is one billionth of an ETH. One gwei is also one billion wei, wei being the smallest unit.
A fee of 12 gwei per unit of gas is 0.000000012 ETH per unit. Quoting that in ETH would be unreadable, which is the entire reason the denomination exists.
What to actually do with this
Three practical consequences.
First, waiting works, because the base fee moves with demand and is capped at 12.5 per cent of change per block. A transaction that is not urgent costs less later.
Second, a high max fee is not a high fee. The unused difference is refunded, so the ceiling protects you from a spike rather than committing you to one.
Third, the thing you are choosing is the tip. The base fee is handed to you by the protocol and then destroyed. If you want context on the network this all runs on, we have written on what Ethereum does and how it differs from Bitcoin.
Frequently asked
What is a gas fee?
It is the payment for having a transaction processed on Ethereum, calculated as the amount of computational work your transaction requires multiplied by a price per unit of that work. Ethereum's documentation defines gas itself as the unit that measures the amount of computational effort required to execute specific operations. Gas is therefore a measure of work, and the fee is that measure priced in ETH.
How is a gas fee calculated?
Units of gas used multiplied by the sum of the base fee and the priority fee. The base fee is set by the protocol from the previous block's size relative to its target. The priority fee is the tip you choose. Your wallet also sets a max fee, which Ethereum's documentation says must exceed the base fee plus the tip, and any unused difference between your max and the actual cost is refunded.
Who receives the gas fee?
Only part of it reaches anyone. Ethereum's documentation states that the base fee is destroyed when the block is created, which removes it from circulation. The validator receives the priority fee alone. Since the tip is normally the smaller component, most of what you pay in a typical gas fee is burned rather than paid to a participant, which is not what the word fee usually implies.
Why is the base fee burned instead of paid out?
To remove a conflict of interest. If validators collected the base fee, they would benefit from keeping blocks full so that the base fee rose, since it is calculated from how full the previous block was. Burning it means a validator gains nothing from a higher base fee, so the only part worth competing over is the tip that users choose to offer. It aligns the incentive with including transactions rather than congesting the network.
What is gwei?
A denomination of ETH used because ETH is too large a unit for fee pricing to be readable. One gwei is one billionth of an ETH, and one gwei equals one billion wei, wei being the smallest unit. A base fee of 10 gwei per unit of gas is 0.00000001 ETH per unit, which is why nobody quotes gas prices in ETH.
Why does a simple transfer cost less than a swap?
Because gas measures work and the two require different amounts. A plain ETH transfer is a fixed operation at 21,000 gas units. A token swap executes contract code, reads and writes storage and may interact with several contracts, each operation carrying its own gas cost. At the same gas price, the difference in your final fee comes entirely from the number of units consumed, not the price per unit.
How fast can gas prices change?
The base fee can rise or fall by up to 12.5 per cent per block, a limit set by the protocol. That cap is why congestion shows up as a climb over several blocks rather than an instant jump, and why the fee falls back in the same stepped way once demand eases. The tip can change as fast as users decide to change it, since it is chosen per transaction.
What happens if I set the gas limit too low?
The transaction runs out of gas before completing. The work done up to that point is not free, so the fee for the consumed gas is still taken, but the transaction does not succeed. This is why the gas limit and the gas price are separate settings: the limit caps how much work you will pay for, and setting it below what the operation genuinely needs wastes the fee without producing the result.
Is the max fee what I will actually pay?
No, it is a ceiling rather than a price. Ethereum's documentation says the max fee must exceed the sum of the base fee and the tip, and that any unused difference is refunded. Setting a high max fee protects a transaction from failing when the base fee climbs between submission and inclusion. It does not commit you to paying the higher amount if the base fee stays low.
Do other blockchains have gas fees?
Most charge for computation in some form, but the terminology and the mechanics differ. Gas is Ethereum's term and the base fee burn comes from EIP-1559 specifically, so the detail that most of the fee is destroyed is not a general property of blockchains. On any given network the questions worth asking are the same: what is being measured, who sets the price, and who ends up with the money.
Sources, and what is behind them
- Gas and fees, ethereum.org developer documentationDocumentationIndependent of vendor
- What is Ethereum? A plain explanation, BTC NewzPress reportIndependent of vendor