> For the complete documentation index, see [llms.txt](https://antonioru.gitbook.io/deep-waters/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://antonioru.gitbook.io/deep-waters/validators/iscreditcard/isdiscover.md).

# isDiscover

isDiscover ::  a → Boolean

Reports whether the received value is a valid credit card number and is a Discover card

```javascript
import isDiscover from 'deep-waters/credit-cards/isDiscover';

isDiscover(6011583945260254); // Discover → true

isDiscover(347190259623701); // American Express → false
isDiscover(4286124395547263); // VISA → false
isDiscover(38716394960899); // Diners Club → false
isDiscover(3528701379615495); // JCB → false
isDiscover('6011-5839-4526-0254'); // Credit card format → false
isDiscover("foo"); // → false
isDiscover(undefined); // → false
```

{% hint style="warning" %}
Please note, **isDiscover** assumes the receiving value is a number or a string without the usual dashes. It only evaluates the credit card number, not its format.
{% endhint %}