H5P wants to change the world of interactive content so that when you use our service you own the content you create, you're not just renting it from the authoring tool. Most tools today will not let you edit your own content if you stop paying for the tool. H5P is free and open source. H5P.com is one of over 40,000 websites with H5P support.
If you choose to or have to leave H5P.com you can export all your content and import it somewhere else (if the content type and its version are supported on the H5P alternative). All content on H5P.com can be exported as H5P files and most can be imported to any other H5P-enabled site at any time. The site you import to may be a Drupal, WordPress, or Moodle site for instance.
Most of your content will be editable in the new solution and the content itself will work the same way.
The .h5p file format is also perhaps the easiest to convert to other formats. It documents itself and is super simple. More about the H5P file format.