You can use your browser’s built-in developer tools to locate the direct source URL of the profile image hosted on Facebook's Content Delivery Network (CDN).
Facebook's privacy model is enforced , meaning the content never even reaches your device unless you're authorized to see it. When a user sets their profile to private or "locked":
Facebook Help Center explicitly states that third-party apps cannot show who views your profile or reveal locked content. Summary Checklist for Safe Viewing Always use reputable browsers (Chrome, Firefox).
Go to Settings → Privacy → Limit Past Posts to change old public posts to friends-only.
Sites often force you through endless ads without ever showing a photo.
If you can see the small thumbnail of the Facebook profile picture, you can take a screenshot of it and upload it to a reverse image search engine like Google Images or TinEye. If the user has used that same photo on a public blog, a company website, or an open forum, the search engine will find the full-sized version elsewhere on the web. Protecting Your Own Profile Picture