# How to calculate GWEI back to ETH/USD?

According to Owlracle, right now the recommended Ethereum fees are:

According to them, an Ethereum fee of 90.73 GWei is equal to roughly 7.7 USD. Can anyone explain how they get to that number?

• According to this site, 90.73 GWei = 0.00000009073 ETHER
• And 0.00000009073 ETHER is 0.00000009073 x 1093.64 = 0.0000992259572 USD

What am I missing? How are they getting to 7.7 USD?

The cost of transactions is calculated as: `gas Price * gas Amount * Ether fiat price`. It has a few more ingredients (such as 'miner tip'), but this is the most important part of the formula.

What you are missing in your calculations is the gas amount. Each transaction requires a different amount of gas, depending on the transaction complexity. The site you are using is a bit weird: it doesn't say for which kind of transactions the price is.

If you have a look at some other site, for example https://etherscan.io/gastracker , you can see that it lists different typical transactions. And if you hover over the question mark, it shows what 'gas limit' is used for the calculation. Gas limit is the maximum amount of gas the transaction is allowed to use, so you can think of it as the gas amount.

• Gas price x gas amount x ether fiat price, but in what units? I have a gas price in wei = 23709966458 and using 31 gwei for the transaction... how much ether am I spending? Commented Jul 1, 2022 at 9:51
• Sorry, you gave me the `gas price` and `ether price` but I don't know how much gas you used. Gas is not measured in weis, it's its own unit. Commented Jul 1, 2022 at 12:53
• Okay no, I am still confused. Going to update my question. Commented Jul 2, 2022 at 12:01
• What is the unit of `gas Amount` is it `gwei`? Commented Dec 24, 2023 at 14:23

Owlracle API uses the average gas used in the recent blocks to calculate the estimated fee.

So if the fee is:

``````gas price (in ether) * gas amount * ETH price
``````

And if we are getting `90.73 GWei` for fast speed, `\$7.72` for an estimated fee, `\$1037` ETH price (at the time of your question), that means that at the time of the estimations, the average gas used was `7.72 / (90.73^-9 * 1037) =~ 82051`.

You can use Owlracle API to get all kinds of gas related information, like the average gas used to perform the fee calculation.

At the time of my writing, this is the response I got from /gas endpoint:

``````{
"timestamp":"2022-07-26T18:52:11.505Z",
"lastBlock":15219809,
"avgTime":14,
"avgTx":208.08,
"avgGas":77433.83295590722,
"speeds":[{
"acceptance":0.355,
"gasPrice":16,
"estimatedFee":1.7002611305126285
},{
"acceptance":0.6,
"gasPrice":19.835912411,
"estimatedFee":2.1078894287922707
},{
"acceptance":0.9,
"gasPrice":26.272281325,
"estimatedFee":2.7918586716743947
},{
"acceptance":1,
"gasPrice":32.092197568,
"estimatedFee":3.4103197573501443
}],
"baseFee":17.338222816440013
}
``````