> For the complete documentation index, see [llms.txt](https://soufatn.gitbook.io/rxjs-book/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://soufatn.gitbook.io/rxjs-book/summary/helpers/is_promise.md).

# isPromise

A function which determines whether the object is a `Promise`.

## Arguments

1. `p` *(Any)*: The object to determine whether it is a promise.

## Returns

*(Boolean)*: `true` if the object is a `Promise` else `false`

## Example

```javascript
var isPromise = Rx.helpers.isPromise;

var p = RSVP.Promise(res => res(42));

console.log(isPromise(p));
// => true
```