This Geometry calculator contains plane (2D) equations  Circles for lines, curves, circles, ellipse, triangles, and polygons. These formulas are for area, perimeter (circumference), segment lengths and arc lengths.

Instructions

This calculator has length and area equations for a large number of plane geometric shapes.  The formulas for the different shapes are grouped in tabs for each shape.  

1. choose your shape and select the appropriate tab (e.g. polygon)
2. choose the formula you wish and click on the formula's button (e.g. area) 
3. enter your parameters. Note: most formulas provide options for the units of the inputs such as inches or centimeters.
4. the answer will be provided.  Note: formula outputs also have units that can be automatically converted via the pull-down menu (e.g. square meters to square miles) 

 Polygon and Quadrilateral  Parabola & Ellipse

General Information

Plane geometry typically refers to  shapes, lines, curves, points and measures of objects in a two dimensional plane, hence "plane" geometry.  The complete library of plane geometry calculators and equations can be found in the vCalc (2D) - Plane Geometry library.