This tool is also available with API version.
How using the API?
Test this API (JSON):
Correct Facebook URL
Make sure the Facebook URL are correct and valid:
FAQ (Frequently Asked Questions)
What is Facebook ID
Facebook Numeric ID is some random numberic for your Facebook account. This is created when you Sign Up for Facebook.
What is the use of Facebook ID
Some plugin like Yoast SEO allow you to access Facebook Insights for your site, you need to specify a Facebook Admin. This can be a user. If you have an app for your site, you could use that as well.