This is a genuinely reasonable question, and the honest answer has more nuance than a flat yes or no. This isn't legal advice — laws vary by country and situation — but here's a clear-headed breakdown of the actual distinctions that matter.

The Core Distinction: Personal Use vs. Redistribution

The single biggest factor is what you do with the video after downloading it:

Facebook's Terms of Service vs. Copyright Law

These are two separate things that people often conflate:

Ownership Doesn't Change When You Download

Whoever created and posted a video retains copyright over it regardless of whether someone else downloaded a copy. Downloading a file doesn't grant any rights to that content — it's still their work, and using it beyond personal viewing (especially commercially, or in a way that implies you created it) can create real legal exposure.

A Practical Framework

Facebook's Own Download Button

Worth noting: some Facebook videos include a built-in download option directly from the poster, when they've enabled it. When that option exists, the poster has explicitly permitted downloading — a much clearer case than a third-party tool pulling a video that didn't offer one.

FAQ

Can I get in legal trouble just for downloading a public video? For personal, non-redistributed use, this is very low-risk in most contexts — but it's not a blanket legal guarantee, and laws differ by country.

Does crediting the creator make redistribution legal? Credit is good practice but doesn't automatically satisfy copyright law — permission from the rights holder is the actual requirement for redistribution.

What about downloading my own business's videos for backup? No concerns at all — it's your own content.

Should I ask before reposting someone else's downloaded video? Yes — asking the original poster directly is the safest and simplest way to avoid any ambiguity.

For the related question of what technically can and can't be downloaded in the first place, see why can't I download Facebook videos.

Legality and access are related but different questions — see can you download private Facebook videos for the access side specifically.