The best open source alternative to Cantor is Jupyter, which is both free and Open Source. If that doesn't suit you, our users have ranked five alternatives to Cantor and four of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Cantor are Beaker (Free, Open Source), Kajero (Free, Open Source) and Starboard (Free, Open Source).
The Beaker Notebook is a new open source tool for research and data science. It's advanced UI allows you to focus on your data and your science, instead of getting frustrated by your tool. We designed it to be polyglot from the ground up.
Starboard brings cell-by-cell notebooks to the browser, no code is running on the backend! It's probably the quickest way to visualize some data with interactivity, do some prototyping, or build a rudimentary dashboard. Features