> ## Documentation Index
> Fetch the complete documentation index at: https://docs.formo.so/llms.txt
> Use this file to discover all available pages before exploring further.

# Chain event

> Reference for the chain event emitted when a user switches blockchain networks, capturing the new chain ID and wallet address in the payload.

The `chain` event is emitted whenever the user's chain network changes.

## Properties

| Property | Type | Description |
| :- | :- | :- |
| `chain_id` | Number | Chain ID of the network the user switched to. |

## Sample Payload

Here’s the payload of a typical call with most common fields removed:

```json theme={null}
{
    "type": "chain",
    "address": "0x8e6ca77a7e044ba836a97beb796c124ca3a6a154",
    "properties": {
        "chain_id": 1
    }
}
```


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