Free Tools

Interactive tools for test-day math

Small, fast tools we built for our own sessions. No account, no download. Use them in class, at home, or on your phone.

FreeGeometry

Cross Section Lab

Slice a cube, sphere, cylinder, cone or pyramid with a plane you control, and see the cross section named, measured and drawn in true shape.

  • Five solids with real dimensions in cm
  • Tilt, spin and slide the cutting plane live
  • Names the shape: trapezoid, regular hexagon, ellipse, parabola, hyperbola
  • Perimeter and area of every section
Open Cross Section Lab

More tools are on the way. Have a request? Tell us what would help.