> For the complete documentation index, see [llms.txt](https://developers.munzen.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developers.munzen.io/payment-widget/integration-guide-for-payment-widget/params-for-channel-widget.md).

# Params for Channel Widget

### Available Params

Here is a list of available params for the channel payment widget:

```json
{
  // Required params
  client_key: string;
  customer_external_id: string;
  signature: string;
  timestamp: number;
  
  // Optional params
  external_id: string;
  external_data: Record<string, string>;
  
  // See full list of currencies here: 
  // https://developers.munzen.io/api-overview/currencies-confirmations-and-limits#sandbox-limitations
  pay_currency: 'BTC' | 'ETH' | 'BCH' | 'USDTERC20' | 'USDTTRC20' | 'LTC';
  price_currency: 'EUR' | 'UAH' | 'USD';
  // String representing float number, for example: 1000.5 
  price_amount: string;
 
  // Theme is purely presentational parameter no used in signature generation
  // It has 2 options, "dark" or "light" -
  // choose what better suits for your application look & feel
  theme: 'dark' | 'light';
};
```

* `client_key` - use your API\_KEY here

Example of params:

```typescript
const API_KEY = 'j6OOj3EPVLQh18IjxWZ1XhohgXx7TuM1eufrQ3lv';

const params = {
    client_key: API_KEY,
    customer_external_id: 'johnny@email.com',
    signature: 'a123b0f6728cca721a9db6a994a39ff19387c104f8c9a2b95beb1576e1fd8079',
    timestamp: 1687778100,
    
    // User will be asked to pay 100.5 EUR via ETH transfer
    pay_currency: 'ETH',
    price_currency: 'EUR',
    price_amount: '100.5',
}

// Generating URL params
const widgetUrlParams = new URLSearchParams(params);
const queryString = widgetUrlParams.toString();

// Example usage with URL
const url = new URL('https://sandbox-payment-widget.munzen.io/channel');
url.search = queryString;

console.log(url.toString());
```

Here is an example of how to generate the signature:

{% embed url="<https://runkit.com/kirart/64996dca7412f20008c0073a>" %}
TypeScript example of generating signature
{% endembed %}

### Result

As a result, you will receive the following link:

{% code overflow="wrap" %}

```url
https://sandbox-payment-widget.munzen.io/channel?client_key=j6OOj3EPVLQh18IjxWZ1XhohgXx7TuM1eufrQ3lv&customer_external_id=johnny%40email.com&signature=a123b0f6728cca721a9db6a994a39ff19387c104f8c9a2b95beb1576e1fd8079&timestamp=1687778100&pay_currency=ETH&price_currency=EUR&price_amount=100.5
```

{% endcode %}

<figure><img src="https://2310310478-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fzy9JU2WWzumd6if76UjL%2Fuploads%2FFKkg1zw4oPCOeDOEhIop%2Fimage.png?alt=media&amp;token=64a3dfc4-6dfd-4b1c-a620-94de0f6b6435" alt=""><figcaption><p>Here is an example of channel payment widget for ETH</p></figcaption></figure>