Licence, legal & governance
The original page runs the licence text, a redistribution checklist and a patent FAQ together as one long scroll. They're for three different readers, so here they're three sections — jump to the one that's actually yours.
The licence
FFmpeg is free software under the GNU Lesser General Public Licence version 2.1 or later (LGPL). Some optional components — generally the ones that trade legal simplicity for extra performance or format support — are covered by the stricter GNU General Public Licence version 2 or later (GPL) instead. Build FFmpeg with any of those enabled and the GPL governs the whole binary, not just that piece.
There is no proprietary or commercial licence available, at any price — the LGPL/GPL terms are the only ones on offer, for everyone.
Redistributing FFmpeg
If your product links against the FFmpeg libraries and you ship it to anyone else, the LGPL comes with real conditions. This is a working summary, not the licence text itself — read the actual licence before you rely on it.
Keep it LGPL
Build without the --enable-gpl or --enable-nonfree
configure flags, and link to the FFmpeg libraries dynamically rather than statically
— that's what keeps your own code out from under the GPL.
Publish the source you actually shipped
Distribute FFmpeg's source alongside your binaries, on the same server, matching exactly what you compiled — including a note of your exact build configuration and a diff of any changes you made.
Credit it properly
Say your software uses FFmpeg under the LGPL 2.1, in both your "about" screen and your end-user licence agreement — and don't claim ownership over FFmpeg's code or forbid reverse-engineering of it in that agreement.
Don't disguise it
Keep FFmpeg's library file names recognisable (a prefix or suffix is fine; an unrelated renamed copy is not), spell "FFmpeg" correctly, and apply all of the above to every GPL or LGPL library you compiled in alongside it, not just FFmpeg itself.
Patents: what FFmpeg can't tell you
This is deliberately the most hedged section on the site, because the honest answer is genuinely uncertain.
Several of the media standards FFmpeg implements — H.264 and MPEG-4 among them — carry explicit warnings from the standards bodies that some part of a conforming implementation may be covered by a patent somewhere. FFmpeg's maintainers aren't lawyers, haven't gone looking for the relevant patents, and couldn't give a reliable yes or no even if they had — patent law differs by country, and some jurisdictions don't recognise software patents at all.
In practice: a private individual using FFmpeg for their own purposes has little to worry about. A company shipping FFmpeg inside a commercial product has more homework to do — organisations holding patents on codecs like the ones behind MPEG have, in the past, pursued licensing fees from companies that monetised them.
Trademark, funding & governance
"FFmpeg" is a trademark of Fabrice Bellard, who started the project. FFmpeg has no company and no office: it's fiscally hosted by Software in the Public Interest (SPI), a 501(c)(3) non-profit registered in New York that handles donations on behalf of several free-software projects, FFmpeg among them. Recent direct sponsorship has come from Germany's Sovereign Tech Fund, and from hardware donations such as a server contributed by Ampere. The project's own site is hosted by telepoint.bg.