Testnets are designed to mimic the mainnet environment to enable developers to test and troubleshoot applications before deploying contracts to mainnet without any value being at risk.
Typically, it is considered good practice to test any contract code on a testnet before deploying to mainnet - most on-chain applications will have a copy deployed on a testnet to allow developers to troubleshoot.
In this guide, we will show you how to obtain testnet ETH tokens on the Sepolia network to test your Chainlinked smart contracts before deploying them to the mainnet.
What is Sepolia testnet?
Sepolia is the default testnet recommended by Ethereum core developers for smart contract application development. Sepolia was originally launched as a definitive testnet in October 2021 by Ethereum core developers. The network later transitioned to a proof-of-stake consensus mechanism to simulate the operating environment of the Ethereum mainnet.
Sepolia uses a set of authorized validators. Because it is a relatively new test network with a small state, the network synchronizes quickly and requires less storage space to run nodes than mainnet or other testnets. These features are useful for developers who want to interact directly with the network and run nodes.
Compared to other Ethereum testnets such as Goerli, the total supply of testnet ETH tokens on the Sepolia testnet is uncapped, making it more likely that developers using Sepolia will continue to have access to testnet tokens in the future.
How to get Sepolia testnet ETH
Using the Chainlink testnet faucet , you can request testnet ETH tokens to test your Chainlinked smart contracts on Sepolia.
- Go to https://faucets.chain.link/sepolia.
- Make sure the Ethereum Sepolia network is selected as this is where you want to receive testnet ETH.
- Click "Connect Wallet" so that the faucet app can detect the selected network and your wallet address.
- If you wish to send testnet funds to a different address than the one you connected to, please paste the address into the "Wallet Address" section. Otherwise, this field defaults to the wallet address you connected to.
- Choose whether you want to receive Sepolia Testnet ETH and/or Sepolia Testnet LINK.
- Verify you are human by clicking "Sign in with GitHub" and connecting your valid GitHub account. This step is to prevent spam requests.
- Click Send Request. Tokens are then transferred from the faucet to your specified wallet address.
If you would like to learn more about testing Chainlinked smart contracts, please visit the Chainlink Dev Hub .
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