> For the complete documentation index, see [llms.txt](https://docs.thndr.io/integration/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thndr.io/integration/lightning-iframe/get-balance.md).

# Get balance

## Retrieving User Balance

The Clinch SDK requires you to provide the user's current balance for display within the Clinch web app. You can do this by using the `getBalance` callback function, which should return the user's balance and currency when requested by the iframe.

## **Implementing the `getBalance` Callback**

The `getBalance` function should retrieve the user's balance from your system and return it to the Clinch web app.

Here’s an example which returns $1.00:

```javascript
  function async getBalance() {
    return {
      balance: 100,
      currency: "cents", // Must be either - sats, btc, or cents (USD)
    };
  }
```