GIF Maker is an extension that enables you to create GIF files easily inside your browser. 

This Chrome extension is a great tool that allow users to create GIFs from existing video file(s) or images. The source input has to be provided as an image or a video file. Once it's done, you can click on the - Make GIF - button to create the GIF file.

There are some settings you can change. You can either select the output format, or you can choose between two animation speeds.