Ethers.js – How to Estimate the Gas Price with Ethers.js v6

ethers.js

This question has been asked a hundred times before.
But with the change from v5 to v6 of the ethers.js library it has become unclear again how to do it.
How can I estimate the cost of a transaction like a function call or contract deployment with ethers.js v6?

Best Answer

I had to figure it out too, but it's quite simple:

Ethers v5: myContract.estimateGas.myFunction(param1, param2);

Ethers v6: myContract.myFunction.estimateGas(param1, param2);

Turns out that the function name and .estimateGas have switched places; .estimateGas is now part of the function.

Related Solutions

Gas Price Estimation – How to Estimate Using Ethers.js

Found it! https://docs.ethers.io/v5/api/providers/provider/#Provider-getGasPrice

Hint: the search functionality on docs.ethers.io isn't great - this method didn't show up by searching for "gasprice": https://docs.ethers.io/v5/search/?search=gasprice

Ethers.js – Estimating Gas Cost to Deploy Smart Contract

You'll first need to get the encoded contract deployment data as follows:

const deploymentData = contract.interface.encodeDeploy([<constructor_arguments>])

Then, you could use the data to get the estimated gas limit as follows:

const estimatedGas = await ethers.provider.estimateGas({ data: deploymentData });

Best Answer

Related Solutions

Gas Price Estimation – How to Estimate Using Ethers.js

Ethers.js – Estimating Gas Cost to Deploy Smart Contract

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