How to use the polygon diagonals calculator
Count the diagonals of a polygon and the triangles made by triangulating it. Enter number of sides in the field above; the diagonals, triangles from triangulation are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “number of diagonals in polygon”, “diagonals of octagon”, “polygon triangulation”, “calculate polygon diagonals”, “find diagonals”.
Formula
Variables
- n — Number of sides
Worked example
With number of sides = 8, the calculator gives diagonals ≈ 20 count; triangles from triangulation ≈ 6 count.
Frequently asked questions
What is the polygon diagonals calculator used for?
Count the diagonals of a polygon and the triangles made by triangulating it. It helps with questions such as “number of diagonals in polygon”, “diagonals of octagon”, “polygon triangulation”.
What is the formula for the polygon diagonals calculation?
Diagonals (count) = n × (n-3) / 2. Triangles from triangulation (count) = n-2. Here n is number of sides.
What inputs do I need for the polygon diagonals calculator?
You need number of sides. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the polygon diagonals calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the polygon diagonals result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.