While there are no verified free tools to view private Facebook profiles and photos, there are legitimate methods to access content:

In the vast, interconnected world of social media, curiosity is a powerful driver. We’ve all been there: you search for an old friend, a potential date, or a new colleague on Facebook, only to be met with a generic silhouette and a locked profile. The only clue to their identity is a tiny, pixelated profile picture.

Another theoretical method: steal a friend’s session token and impersonate them. But that requires compromising a mutual friend’s account—a serious criminal act. No website offering a free viewer can do this on demand for arbitrary profiles.