Honest scope: Facebook's own lookup API (Graph API) refuses anonymous ID lookups, so this tool cannot resolve arbitrary vanity usernames (like
facebook.com/zuck) into numeric IDs — no free client-side tool honestly can. What it can do reliably: pull the numeric ID straight out of URL formats that already contain it (profile.php?id=..., /people/Name/ID, numeric page/group URLs). For vanity URLs, it points you to the one method that actually works: viewing the page source. Runs entirely in your browser.
