When comparing Diagrams.net vs Figma, the Slant community recommends Figma for most people. In the question“What are the best mockup and wireframing tools for websites?” Figma is ranked 5th while Diagrams.net is ranked 6th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Rich functionality for a web-based application
Pro Integrates with multiple cloud storage services
Draw.io offers saving files directly to services such as Google Drive, OneDrive or Dropbox along with saving to to computer.
Pro Real-time collaboration
Pro Great flexibility customizing text labels
Pro Completely free
Pro There is also a Desktop version
Pro Good list of different output formats
Draw.io supports export for PNG, GIF, JPEG, PDF, SVG, HTML, and XML.
Pro Internet Explorer 6-8 and touch device support
Draw.io works with every browser (even IE 6) without plugins.
Pro Works in the browser
Pro Allows for real time collaboration
Pro Live previews for mobile
Mirrors your designs to your phone in realtime.
Pro Has all the core functionality you'd expect from something like Sketch
Pro Integrates with Slack
Provides integration with Slack.
Pro Provides a free version
Does not require a paid subscription for use. Can be used freely with a lot of features. The free use allows very limited collaboration.
Cons
Con Import from Visio .vsd is useless
Even simple diagrams get all scattered.
Con Behaves strangely for certain diagram types
For example the snapping function for arrows doesn't work properly for the sequence diagram template.