A Facebook video downloader online is a tool that lets you download videos directly from Facebook without the need for additional software. To use these tools, simply follow these steps:

1. Find the Video: Go to Facebook and find the video you want to download.
2. Copy the Video URL: Right-click on the video and select "Copy video URL" or copy the link from the address bar.
3. Open a Downloader Website: Visit a trusted online Facebook video downloader, like "FBDown.net" or "SaveFrom.net."
4. Paste the URL: Paste the copied video URL into the provided text field on the site.
5. Download: Click the download button to save the video to your device in your preferred resolution.

These online downloaders are user-friendly, fast, and don’t require any installation. Just make sure to use reputable sites and respect copyright laws!