Chains
25 chains can be forked right now.
| Chain | Chain id | Testnet id by default | Native token |
|---|---|---|---|
| Ethereum | 1 | 7357001 | ETH |
| BNB Chain | 56 | 7357056 | BNB |
| Base | 8453 | 7357453 | ETH |
| Arbitrum One* | 42161 | 7357161 | ETH |
| OP Mainnet | 10 | 7357010 | ETH |
| Polygon | 137 | 7357137 | POL |
| Avalanche C-Chain | 43114 | 7357114 | AVAX |
| Linea | 59144 | 7357144 | ETH |
| Scroll | 534352 | 7357352 | ETH |
| Blast | 81457 | 7357457 | ETH |
| Unichain | 130 | 7357130 | ETH |
| World Chain | 480 | 7357480 | ETH |
| Zora | 7777777 | 7357777 | ETH |
| Soneium | 1868 | 7357868 | ETH |
| Ink | 57073 | 7357073 | ETH |
| opBNB | 204 | 7357204 | BNB |
| Mantle | 5000 | 7357000 | MNT |
| Gnosis | 100 | 7357100 | xDAI |
| Celo | 42220 | 7357220 | CELO |
| Sonic | 146 | 7357146 | S |
| Berachain | 80094 | 7357094 | BERA |
| ApeChain* | 33139 | 7357139 | APE |
| Metis | 1088 | 7357088 | METIS |
| Sepolia | 11155111 | 7357111 | ETH |
| Base Sepolia | 84532 | 7357532 | ETH |
* Arbitrum One: ArbOS precompiles such as ArbSys are not emulated, and block.number is the L2 block rather than the L1 one ArbSys would give. ApeChain: An Arbitrum Orbit chain: ArbOS precompiles are not emulated.
How a fork of an L2 behaves
A testnet runs the EVM with Ethereum's rules and the chain's own state. For Ethereum and OP Stack chains (Base, OP Mainnet, Unichain, World Chain and the rest) that is exact: their predeploys and contracts are all there. zkSync is not offered, because it is not EVM-equivalent and a fork of it would be wrong in ways nobody would notice.
Chain ids
A new testnet gets 7357000 + the last three digits of the parent's id unless you choose otherwise — BNB Chain (56) becomes 7357056. You can change it later in the testnet's settings; signed transactions must be signed for whichever id it has.