Testnet

A blockchain network used for testing and development, simulating the main Ethereum network without using real digital assets.

What is Testnet?

A testnet, short for “test network,” is an alternative blockchain environment designed to replicate the functionality of a main blockchain network, such as Ethereum’s mainnet, for testing and development purposes. Testnets allow developers to experiment with smart contracts, decentralized applications (dApps), or protocol upgrades in a risk-free setting, as they use test tokens (e.g., test ETH) that have no real-world value. This enables developers to identify bugs, optimize performance, and ensure security without risking actual funds.

For example, Ethereum testnets like Sepolia, Goerli, and Holesky mimic the mainnet’s consensus rules and network behavior, but operate independently with separate tokens faucets that distribute free test ETH. These networks are widely used by developers to deploy and test smart contracts, by node operators to trial software updates, or by users to practice transactions. While testnets are critical for innovation and stability, they may differ slightly from the mainnet in terms of network activity or validator incentives, and their data does not impact the main blockchain.