# Ethereum
Ethereum is a public permissionless blockchain protocol.
Chainstack currently supports joining the following Ethereum networks:
- Mainnet — public Ethereum mainnet.
- Sepolia testnet — a proof-of-stake public permissioned Ethereum testnet.
- Goerli testnet — a proof-of-stake public Ethereum testnet.
For development purposes on Ethereum testnets, fund your accounts with testnet ether.