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Use ethers.js

In this tutorial, you'll send a transaction of 0.001 ETH from one account to another using the ethers.js JavaScript library.

Prerequisites​

info

Use MetaMask or similar to create an Ethereum account for testing.

Steps​

1. Select your network and verify funds​

To use the Sepolia testnet, ensure that your account has Sepolia ETH. You can use the Infura faucet to add more funds.

2. Create a project directory​

Create a new directory for your project using the command line:

mkdir infura

Change into the new directory:

cd infura

3. Install required packages​

Install the ethers and dotenv packages in the project directory.

info

The dotenv package allows you to use a .env file to securely store private environment variables on your local machine.

Install the ethers package:

npm install --save ethers

Install the dotenv package:

npm install dotenv --save

4. Create a .env file​

Create a .env file in your project directory to store the project and Ethereum account details:

.env
ETHEREUM_NETWORK = "<NETWORK>"
INFURA_API_KEY = "<YOUR-API-KEY>"
SIGNER_PRIVATE_KEY = "<PRIVATE-KEY>"

Replace the following values in the .env file:

  • <NETWORK> with sepolia or the alternative network you are using.
  • <YOUR-API-KEY> with your API key of the web3 project.
  • <PRIVATE-KEY> with the private key of your Ethereum account. A transaction must be signed with the sender's private key. Make sure that you prefix the SIGNER_PRIVATE_KEY value with 0x. The private key you export from MetaMask isn't prefixed with 0x.
danger

Never disclose your private key. Anyone with your private keys can steal the assets controlled by those keys.

5. Create an eip1559_tx.js file​

In the project directory, create an eip1559_tx.js file, which configures and sends the transaction. For example:

Important

To send test ETH to an account of your choice, update line 15 with your selected account.

eip1559_tx.js
const { ethers, parseUnits } = require("ethers");

  async function main() {
    // Configuring the connection to an Ethereum node
    const network = process.env.ETHEREUM_NETWORK;
    const provider = new ethers.InfuraProvider(
      network,
      process.env.INFURA_API_KEY
    );
    // Creating a signing account from a private key
    const signer = new ethers.Wallet(process.env.SIGNER_PRIVATE_KEY).connect(provider);

    // Creating and sending the transaction object
    const tx = await signer.sendTransaction({
      to: "0x618917c657e9F5b346c0141CB14F5D3CED65D449", // Replace with your selected account
      value: parseUnits("0.001", "ether"),
    });
    console.log("Mining transaction...");
    console.log(`https://${network}.etherscan.io/tx/${tx.hash}`);
    // Waiting for the transaction to be mined
    const receipt = await tx.wait();
    // The transaction is now on chain!
    console.log(`Mined in block ${receipt.blockNumber}`);
  }

6. Execute the transaction​

To execute the transaction, run:

node eip1559_tx.js

Example output:

Mining transaction...
https://sepolia.etherscan.io/tx/0x7c5c0061fbda9e01c1bb1269ffc7323107e2116d8f7327ee945aecc7c33d21c8
Mined in block 7587728

You can search for the transaction on a block explorer such as Sepolia Etherscan.

(Optional) Fine tune the transaction details​

To change default values, update the signer.sendTransaction method to include an estimateGas result:

eip1559_tx.js
const limit = provider.estimateGas({
  from: signer.address,
  to: "<to_address_goes_here>",
  value: ethers.utils.parseUnits("0.001", "ether"),
});

// Creating and sending the transaction object
const tx = await signer.sendTransaction({
  to: "<to_address_goes_here>",
  value: ethers.utils.parseUnits("0.001", "ether"),
  gasLimit: limit,
  nonce: signer.getTransactionCount(),
  maxPriorityFeePerGas: ethers.utils.parseUnits("2", "gwei"),
  chainId: 3,
});