# Reference: `sushi/evm` Chain

The EVM chain module exposes EVM-only chain metadata and type guards.

| Export | Purpose |
|---|---|
| `evmChains`, `evmChainIds` | Known EVM chains and IDs. |
| `EvmChainId` | Enum-like EVM chain ID lookup. |
| `isEvmChainId`, `getEvmChainById` | Guard and lookup by ID. |
| `EvmMainnetChainId`, `isEvmMainnetChainId` | Mainnet type and guard. |
| `EvmTestnetChainId`, `isEvmTestnetChainId` | Testnet type and guard. |
| `EvmChainKey`, `isEvmChainKey`, `getEvmChainByKey` | Chain key type, guard, and lookup. |
| `defineEvmChain` | Define an EVM chain object. |

```ts twoslash
import { EvmChainId, getEvmChainById, getEvmChainByKey } from 'sushi/evm'

const ethereum = getEvmChainById(EvmChainId.ETHEREUM)
const base = getEvmChainByKey('base')

ethereum.viemChain
```

EVM chain objects include viem chain metadata and explorer URL helpers. For feature support such as API, V2, or V3 availability, see [EVM Config](/sdk/reference/evm/config).