3D Surface Plotter
Functions of two variables are surfaces, and intuition for them comes from rotating them in your hands. This plotter renders classic surfaces — the saddle x² − y², the ripple sin(r)/r, a Gaussian peak, the monkey saddle and crossing waves — as a colour-graded 3D mesh you drag to rotate. Height colouring and the wireframe make critical points easy to spot: maxima, minima and the saddle points where the surface curves up one way and down the other.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- A saddle point is a maximum along one direction and a minimum along another — the saddle z = x² − y² is the canonical example.
- The ripple sin(r)/r is the 2D analogue of the sinc function, with circular waves that decay like 1/r.
- Level curves are horizontal slices; they bunch together where the surface is steep.
- Runs 100% in your browser — simulations are computed locally on your device.
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