ShareX is a free and open source screen capturing tool for Windows so loaded with features that it may give even commercial screen capture programs a run for their money. The tool is portable too so you can run it on your USB drive without installation.

ShareX has all the necessary features that would expect in a screen capturing tool. It lets you capture fixed areas on the screen, full application windows or even freehand regions. There’s a built-in editor to help you annotate screenshot images. You can create watermarks and they are auto-added to the image after the screen capture is complete.

You can configure the app to auto-upload your screen captures to cloud destination like Google Drive, Dropbox, Picasa, Box, Flickr, Imgur and many more. When the image is uploaded, the shared URL is copied to the clipboard for quick sharing on social networks.

There’s a useful timer mode that will auto-capture screenshots of the selected region on your desktop after ‘n’ seconds and will then upload them to your favorite destination.

The tool can automatically watermark your screenshot images before uploading

ShareX also includes a screen recorder and the screencasts can be either saved as video (MP4) files or as animated GIFs. You can modify the default capture frame rate (FPS) to achieve a balance between the video quality and the video file size.

Alternatives include Greenshot, Bug Shooting, PicPick and Skitch.