This Volume of a Decagon formula,(Vdecagon=5/2 • √(5+2√5) • s2• h) computes the volume a column with a regular decagon face, a polygon with 10 equal sides of length (s) and a height (h). 
Regular Decagon Column
INSTRUCTIONS: Choose units and enter the following:
- (s) - Length of the sides of the decagon
- (h) - Height of the decagon column
Decagon Volume (V): The volume is returned in cubic meters. However, the volume can be automatically converted into many other cubic units via the pull-down menu.
The Math / Science
A regular decagon has ten equal sides and equal angles.
Decagon Calculators
Volume is a three dimensional measurement of the amount of space taken up by an object. 
Volume units are cubic measurements for solid objects such as cubic inches and cubic meters. Fluids have separate volume units such as liters, fluid ounces, cups, gallons, and barrel.
The volume of an object can measured by the liquid it displaces or be calculated by measuring its dimensions and applying those dimensions to a formula describing its shape. Many such calculations are available in the following list of calculators.
In many cases, the calculators are for a column with a geometric shaped base and vertical sides. One basic formula for volume is area times a Height when the volume has vertical sides.
Volume Calculators
- Volume from Area and Height
- Volume of a Cube
- Volume of a Box
- Volume of a Cone
- Volume of a Cone Frustum
- Volume of a Cylinder
- Volume of a Slanted Cylinder
- Volume of a Semicircle
- Volume of a Triangular
- Volume of a Quadrilateral
- Volume of a Pentagon
- Volume of a Hexagon
- Volume of a Heptagon
- Volume of a Octagon
- Volume of a Nonagon
- Volume of a Decagon
- Volume of a Hendecagon
- Volume of a Dodecagon
- Volume of a Paraboloid
- Volume of a Polygon based Pyramid
- Volume of a Pyramid Frustum
- Volume of a Sphere
- Volume of a Sphere Cap
- Volume of a Sphere Segment
- Volume of a Sphere Shell
- Volume of a Oblate Spheroid
- Volume of a Ellipsoid
- Volume of a Torus
- Volume of a Bottle
- Volume of a Chamfer
- Gasket Volume