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A gas limit caps the number of gas units a transaction can consume. A gas price puts a cost on each unit. Neither number alone tells you the final execution fee: you need the gas actually used and the effective price paid. [1][4]
This guide explains Ethereum Mainnet execution fees, including EIP-1559-style fee caps. It is not a current fee quote, a recommended wallet configuration or an all-in cost model for another network.
Separate the quantity from its price
| Field | What it describes | Unit |
|---|---|---|
| Gas limit | Maximum gas available to the transaction | Gas units |
| Gas used | Gas units charged for this transaction | Gas units |
| Effective gas price | Actual price paid for each unit | Usually displayed in gwei per gas |
| Max fee per gas | EIP-1559 ceiling on the per-unit price | Gwei per gas |
| Execution fee | Gas used multiplied by effective gas price | ETH after conversion |
Gas measures computational work; it is not a separate token. One gwei is one-billionth of an ETH. Do not confuse the transaction gas limit discussed here with a block's gas limit, which concerns the block as a whole. [1]
A max fee is not necessarily the price paid
For an EIP-1559 transaction, the block's base fee and the transaction's priority-fee cap determine the effective price, subject to its max-fee cap. Provided the transaction is valid for inclusion: [2]
Effective price = base fee + min(priority-fee cap, max-fee cap − base fee).
The max-fee cap must cover the base fee. A valid cap does not guarantee inclusion or successful execution. The unused gap between a cap and the actual charge is not another fee. Legacy transactions use a gas-price field rather than this pair of EIP-1559 caps. [2]
One fictional receipt, two different amounts
Assume an ordinary EIP-1559 execution with these invented values. They are teaching inputs, not settings to copy or a prediction of network conditions.
0.00056 ETH
40,000 gas × 14 gwei per gas
0.0012 ETH
60,000 gas × 20 gwei per gas
| Input | Illustrative value |
|---|---|
| Transaction gas limit | 60,000 gas |
| Gas used | 40,000 gas |
| Base fee | 12 gwei per gas |
| Priority-fee cap | 2 gwei per gas |
| Max-fee cap | 20 gwei per gas |
The effective price is 12 + min(2, 20 − 12) = 14 gwei per gas.
- Execution fee: 40,000 × 14 = 560,000 gwei = 0.00056 ETH.
- Gas-fee ceiling from the two caps: 60,000 × 20 = 1,200,000 gwei = 0.0012 ETH.
The second amount is not the receipt's charge. It also excludes any ETH sent as transaction value. For an EIP-1559 transaction, your balance must cover both the ETH sent and gas limit × max fee per gas. [2]
Why a failed execution can still cost gas
Reversing an operation's state changes does not erase the computation already performed. A contract can use REVERT to abort and undo its changes without consuming all remaining gas. That is different from an out-of-gas exception, which consumes the gas available to the failing execution. A failed transaction therefore need not have used exactly its full transaction gas limit. [3]
Also distinguish an execution failure from rejection before block inclusion. An invalid transaction rejected before execution does not consume on-chain gas merely because a wallet displayed an error. [1]
These distinctions explain a fee; they do not diagnose the cause of a specific failed transaction or justify resubmitting it.
Read the receipt, not just the estimate
Ethereum's transaction receipt separates gasUsed, effectiveGasPrice and status. The gasUsed field belongs to that transaction; cumulativeGasUsed includes the block's transactions up to that point. Using the cumulative figure can overstate the individual fee by including earlier transactions in the block. A pending transaction does not yet have an execution receipt. [4]
Read the fields together:
- Is there a receipt, or only a pre-execution estimate?
- Does status indicate success or failure?
- Are you multiplying this transaction's gas used by its effective unit price?
- Is the price shown in wei or gwei, and has the final fee been converted to ETH or a separate fiat value?
A gas calculation is not a complete cost comparison. Platform charges and other funding costs are separate questions, covered in our prediction market fees guide. A fee figure also says nothing about the authority granted by a request; see what a token approval allows.
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Sources
Sources checked on 22 October 2026. This is the evidence-check date, not their publication date. No wallet was connected and no transaction was submitted for this guide.
- Ethereum: Gas and fees.
- EIP-1559: Fee market change, especially transaction validation and fee accounting.
- EIP-140: REVERT instruction.
- Ethereum JSON-RPC: eth_getTransactionReceipt.
Educational guide from HypaForecast.
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