Gifski

You may need ffmpeg to convert video to PNG frames first (Homebrew installation includes built-in video conversion, but other versions don’t). In your favourite command line/terminal, run:

ffmpeg -i video.mp4 frame%04d.png

This command takes a file named “video.mp4” and makes files “frame0001.png”, “frame0002.png”, “frame0003.png”, etc. from it (%04d makes the frame number. Windows may need %%04d). You can usually drag’n’drop files into the terminal window to avoid typing the paths.

and then make the GIF from the frames:

gifski -o file.gif frame*.png