Regular Hexagon Calculator: choose one known value, enter it, and this tool calculates all major hexagon dimensions instantly.
What this hexagon calculator solves
This page is a practical hexagon dimension calculator for a regular hexagon (all six sides equal, all interior angles 120°). If you know just one measurement—such as side length, apothem, perimeter, or area—you can quickly compute the rest.
This is useful for geometry homework, CAD layouts, woodworking, CNC machining, tile planning, and mechanical design where hexagonal parts are common.
Hexagon dimensions included
- Side length (s): one edge of the hexagon.
- Apothem (a): distance from center to midpoint of a side (also the inradius).
- Flat-to-flat distance: distance between opposite parallel sides.
- Corner-to-corner distance: distance between opposite vertices (equals diameter of circumcircle).
- Perimeter (P): total length around the hexagon.
- Area (A): enclosed 2D surface.
Core formulas for a regular hexagon
All relationships below are based on side length s:
- Perimeter: P = 6s
- Apothem: a = (√3 / 2)s
- Flat-to-flat: F = √3s
- Corner-to-corner: C = 2s
- Area: A = (3√3 / 2)s2
Because these formulas are linked, the calculator can work backwards from any one of the inputs.
How to use the calculator
Step-by-step
- Select the dimension you already know.
- Enter a positive value.
- Click Calculate to see all derived dimensions.
- Click Clear to reset and run another case.
Example: calculate from area
Suppose your regular hexagon area is 200 square units. The calculator first finds side length using:
s = √(2A / (3√3))
Then it computes perimeter, apothem, flat-to-flat, and corner-to-corner values from that side length. This is especially helpful when reverse-engineering geometry from an area requirement.
Common applications
- Designing hex nuts, sockets, and tool interfaces.
- Planning honeycomb structures and hex grids.
- Creating game maps and tabletop terrain tiles.
- Laser cutting and 3D modeling for decorative panels.
- Estimating materials for patterned flooring.
Important notes and mistakes to avoid
1) Regular vs. irregular hexagon
This calculator is for regular hexagons only. If side lengths or angles vary, these formulas no longer apply directly.
2) Unit consistency
Keep your units consistent. If your input is in millimeters, all linear outputs are millimeters; area will be square millimeters.
3) Area is squared units
Area grows with the square of side length. Doubling side length multiplies area by four—not two.
Quick FAQ
Is a hexagon’s circumradius equal to side length?
For a regular hexagon, yes. The radius from center to any corner equals the side length.
What is the interior angle of a regular hexagon?
Each interior angle is 120°.
Can I use decimal inputs?
Yes. The calculator supports decimal values and returns rounded outputs for readability.