A GIF is a short animation made of up to 256 colours per frame that loops forever and plays anywhere an image can, including email, chat apps, docs and README files. Video to GIF lets you pick the part of a video you want on a preview player, then builds the GIF from just that part.
It uses FFmpeg's two-pass method in your browser. The first pass studies the selected frames and builds the best 256-colour palette for them; the second pass draws every frame with that palette and a fine dither, which avoids the banding and grainy look of quick converters. You choose the width (320 to 800 px, height follows the video's shape) and the frame rate (8 to 24 fps), and the tool shows a likely file size before you start.
Limits: up to 30 seconds per GIF and videos up to 500 MB. GIF is an old, inefficient format, so long or wide GIFs get large fast: 10 seconds at 480 px can easily pass several MB, and the tool shows a likely size before you start. GIFs have no sound. If you need sound or a smaller file, keep the clip as MP4.