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Gas Fee Estimator

A transaction fee is gas used multiplied by the price paid per unit of gas. This converts gas limit and gwei price into native tokens and fiat, so you can see whether a swap is worth making before you sign it.

Gas
0.000525 ETH
USD
$1.84

How to use the Gas Fee Estimator

  1. Enter the gas limit for your transaction type.
  2. Enter the current gas price in gwei, including any priority tip.
  3. Enter the token's fiat price.
  4. Compare the fee against the transaction value to judge whether it is worth executing.

How the calculation works

Fee = gas units × gas price. Gwei is 10⁻⁹ of the native token, so the fee in tokens is (gas × gwei) ÷ 10⁹, then multiplied by the fiat price. Typical gas limits are stable by transaction type: a plain transfer is 21,000, a token transfer around 45,000–65,000, and a DEX swap 120,000–250,000 depending on the route.

Under EIP-1559 the gas price splits into a base fee, which is burned and adjusts algorithmically with block fullness, and a priority tip that goes to the validator. Raising the tip buys faster inclusion but does not change the base fee. Unused gas is refunded, so setting a generous limit costs nothing extra — but setting it too low risks the transaction reverting with the fee still charged.

Formula
Fee (token) = gas limit × gas price (gwei) / 1e9 ; fee (fiat) = fee × token price

Source: EIP-1559 fee market: base fee plus priority tip, with gwei as 10⁻⁹ of the native unit.

Worked example

A DEX swap with a 180,000 gas limit at 28 gwei, token price 2,450.

  1. Fee in tokens = 180,000 × 28 / 1e9 = 0.00504.
  2. Fee in fiat = 0.00504 × 2,450 = 12.35.
  3. On a 300 swap that is 4.1% of value.
  4. On a 5,000 swap it is 0.25%.

About 12.35 per swap — negligible on large trades, prohibitive on small ones.

Frequently asked questions

Why do fees spike?+

The base fee rises when blocks are full. Popular mints and volatile markets push demand for block space up sharply.

Do I pay for unused gas?+

No. The limit is a ceiling; unused gas is refunded. Only the gas actually consumed is charged.

What happens if the limit is too low?+

The transaction runs out of gas and reverts, and the gas consumed is still charged.

How can I pay less?+

Transact during quieter hours, batch actions, or use a layer-2 network where fees are orders of magnitude lower.

Last reviewed August 31, 2026. We review this page whenever the underlying formula, tax year, published rate or standard changes.

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