Calculator.com is a great resource for all subjects that call for a calculator. The collection of chemistry calculators is broken down into different fundamental concepts. It’s helpful for all chemistry levels, from introductory chemistry, to higher level endeavors in such topics as quantum numbers and advanced stoichiometry.

A resource for educators and students.  ChemCollective provides content for pre-labs, for alternatives to textbook homework, and for in-class activities for individuals or teams. Students can find the site helpful for reviewing and learning chemistry concepts via  virtual labs, simulations, and tutorials.