Computational knowledge engine — solve equations, plot functions, convert units, look up chemical compounds, analyze data. Like Google but for computation.

Visualization software for abstract algebra. Explore symmetry groups, Cayley diagrams, and multiplication tables interactively. A mathematician's playground.

Randall Munroe's legendary webcomic about science, math, language, and love. Hover over each comic for a hidden alt-text punchline.

Math solver with step-by-step explanations for complex problems.

A retired math teacher has built full-blown math lessons for every grade, from 1st to 12th, and includes AP math lessons — all for free, relying only on donations.

Desmos.com's calculator is a great tool for anyone in high school or university who is studying any subjects related to maths. The online graphing webpage will take any function you give it and display a clean graph. You can zoom in and out of the graph as much as you want and there is a helpful mathematical keyboard at the bottom of the screen to input more complex function symbols.