Testnet
Also known as: Development Network, Blockchain Testing Environment, Smart Contract Sandbox
A public blockchain network used for testing applications and smart contracts without risking real assets.
A testnet is a separate blockchain environment that mimics the conditions of a mainnet, allowing developers to test applications, smart contracts, and infrastructure upgrades with no financial risk. Testnets use valueless tokens for experimentation and debugging. Popular testnets include Goerli and Sepolia (Ethereum), Fuji (Avalanche), and Mumbai (Polygon). They’re essential for validating contract logic, performance, and integrations before mainnet deployment. Some testnets simulate specific consensus or fee models. Faucet services provide developers with test tokens to simulate real-world use cases.