# eth_chainId - Etherlink RPC Method

Returns the chain ID used for transaction signing on Etherlink.

## When to Use This Method

Identify Etherlink mainnet. The expected chain ID is 42793, hexadecimal 0xa729.

## Best Practices

Keep the recorded block height and address together when reproducing a historical example. Preserve RPC errors instead of replacing them with empty results.

## Request Parameters

This method accepts no parameters.

## Request Example

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_chainId",
  "params": []
}
```

## Response Fields

This method returns no documented fields.

## Successful Response

```json
{
  "jsonrpc": "2.0",
  "result": "0xa729",
  "id": 1
}
```

## Code Examples

```bash
curl -X POST "https://api-etherlink-mainnet.n.dwellir.com/YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  --data-raw '{"jsonrpc":"2.0","id":1,"method":"eth_chainId","params":[]}'
```