ShareX

ShareX is an ad-free open-source tool that is perfect for anyone looking to share screenshots on the web, with tons of customization, such as a paid software splash screen.

ShareX is primarily aimed at developers and power users, so the average consumer will be pleased with its many powerful tools and editors.

Some of the benefits of ShareX are - 

• Full-screen image or navigation, window, monitor, area, hands-free.
• It supports the sharing of many URL services, including keyboard shortcuts for easier and faster navigation.
• Import existing videos, music, or photos.
• Allow custom watermarks and color effects.