What is a testnet? A testnet faucet provides web3 developers with free tokens for deploying, testing, and optimizing smart contracts on test blockchains such as Sepolia, Goerli, and Mumbai. Because smart contracts on public, mainnet blockchains like Ethereum and Polygon require gas fees to run smart contracts, testnets provide blockchain developers with a network that mirrors production blockchain environments without requiring gas fees that cost real money. Get Testnet Tokens! blockchain testing tools bsc testnet info3 ethereum test coin free bitcoin mining software 2022 linea goerli testnet faucet google sepolia testnet test smart contract solidity testnet ether