At this time, Hotjar does not have a public API. We actively keep track of this common request and make sure to upvote it within our Suggest a Feature tool whenever it is raised.
To make sure your voice is heard, head to our Suggest a Feature tool and upvote making Hotjar's API public. Every quarter, our Product team reviews these requests to help them prioritize what to build next.
If you had any further ideas about what you'd hope to see with a public API from Hotjar, feel free to add a comment when voting.