> 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/observable/observable_methods/frompromise.md).

# fromPromise

Converts a Promises/A+ spec compliant Promise and/or ES2015 compliant Promise to an Observable sequence.

## Arguments

1. `promise` *(`Promise`)*: Promises/A+ spec compliant Promise to an Observable sequence.

## Returns

*(`Observable`)*: An Observable sequence which wraps the existing promise success and failure.

## Example

### Create a promise which resolves 42

### Create a promise which rejects with an error