GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.
Ray.so - Create beautiful images of your code
GitLab - Create, review and deploy code together with GitLab open source git repo management software | GitLab
Codeimg.io - Create and share images of your source code
BitBucket - Bitbucket is a free code hosting site for Mercurial and Git. Manage your development with a hosted wiki, issue tracker and source code.
CodeZen - Generate shareable and elegant image from your source code.