ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
Screenshot Bin - Generate website screenshots and thumbnails at scale, right from your app. Screenshots as a service.
Thum.io - A real-time website screenshot generator
Headers.me - Create social cover images that get you followers
Picmaker - Design the Future
Slickr - Powerful cover image generator for your Hashnode blog