Dillinger

Dillinger is a cloud-enabled, mobile-ready, offline-storage, AngularJS powered HTML5 Markdown editor. source

With Dillinger, you can import a HTML file and it will automatically converted to Markdown.

You can also use this online tool to import and save files from Google Drive, GitHub, Dropbox and One Drive. You can use it
to export documents as Markdown, HTML and PDF.

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