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# eth_chainId

# `eth_chainId`

Returns the chain ID of the connected network. Linea Mainnet is `0xe708` (59144). Linea Sepolia is `0xe705` (59141).

## Parameters

None.

## Returns

Hexadecimal value of the chain ID.

## Example

### Request

```bash
curl https://rpc.linea.build \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_chainId","params":[],"id":1}'
```

### Response

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xe708"
}
```