Screenshot Bin - Generate website screenshots and thumbnails at scale, right from your app. Screenshots as a service.
Slickr - Powerful cover image generator for your Hashnode blog
Ui Thumbnail Generator - A simple way to generate thumbnail. For docs and demos.
Canva Pro - Millions of design assets, templates and images all in one
FilePreviews - Thumbnails and metadata for almost any kind of file
Figen - Free post cover & background generator tool