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Regular polygon perimeter calculator

Compute the perimeter of a regular polygon from its number of sides and side length.

Related tools

All Geometry tools →
Regular polygon area calculatorCompute the area of a regular polygon from its number of sides and side length.Regular polygon calculatorEvery measure of a regular polygon from the number of sides and the side length: the area, perimeter, interior and exterior angles, the sum of interior angles, the apothem (inradius), the circumradius and the number of diagonals. One entry, the full geometry — for triangles through many-sided polygons.Perimeter calculatorCompute the perimeter of a rectangle, square, circle or triangle.Ellipse perimeter calculatorEstimate the perimeter of an ellipse from its two semi-axes (Ramanujan's formula).Polygon diagonals calculatorHow many diagonals a polygon has, from its number of sides: n·(n−3)/2 — because each vertex connects to all others except itself and its two neighbours. It also names the polygon and gives the number of triangles it splits into and the sum of its interior angles.Irregular polygon area calculatorThe area of any polygon — regular or not, convex or concave — from its corner coordinates. Enter the vertices in order and the shoelace formula returns the exact area, plus the perimeter, the centroid and whether the points run clockwise or counter-clockwise, with a drawing of the shape. Ideal for land plots and CAD sketches.Equilateral triangle calculatorCompute the area, height and perimeter of an equilateral triangle from its side.Triangle area calculator (Heron's formula)Compute a triangle's area from the length of its three sides.

The Regular polygon perimeter calculator turns Number of sides, Side length into Perimeter, instantly and for free. For instance, with Number of sides = 6 and Side length = 10 it returns Perimeter = 60.

How to use it

  1. Enter your values: Number of sides, Side length.
  2. Read the result instantly: Perimeter.

Frequently asked questions

How does the Regular polygon perimeter calculator work?

It takes Number of sides and Side length and derives Perimeter from them. The calculation is live as you type, so the result updates on every change.

Which values does the calculator ask for?

2 values: Number of sides and Side length. Nothing else is required — no account, no file upload.

What does a typical calculation look like?

With Number of sides = 6 and Side length = 10, the calculator returns Perimeter = 60. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

How much does the result change with different inputs?

It moves a lot. Using Number of sides = 12 and Side length = 20 instead, Perimeter goes from 60 to 240 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Number of sides = 3 and Side length = 5, Perimeter comes out at 15. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Homework and site work alike: how much paint a wall takes, how much water a tank holds, whether a corner is square — and, on the coordinate side, the slope between two points, the distance across a plan, the midpoint of a span.

What is the most common mistake?

Mixing units inside one shape. Entering a length in centimetres and a width in metres gives an area wrong by a factor of a hundred, and the result looks perfectly plausible.

What is the difference between the Regular polygon perimeter calculator and the Regular polygon area calculator?

This one returns Perimeter; the Regular polygon area calculator returns Area. That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Regular polygon calculator is the closest one after this: Every measure of a regular polygon from the number of sides and the side length: the area, perimeter, interior and exterior angles, the sum of interior angles, the apothem (inradius), the circumradius and the number of diagonals. One entry, the full geometry — for triangles through many-sided polygons.

What else is worth having open alongside it?

Perimeter calculator and Ellipse perimeter calculator — they come up in the same task often enough to be worth a second tab.

Further reading

All guides →
How-toHow to Find the Area of a Triangle: Base × Height and Heron's FormulaTwo reliable ways to find a triangle's area: half base times height when you know the height, and Heron's formula when you only know the three sides.ExplainerThe Flat Pattern of a Cone Is a Sector, Not a CircleRoll a 50 mm cone 80 mm tall and its pattern is a 190.8° slice of a 94 mm circle. Flatten a nearly cylindrical lampshade and the pattern radius runs to 839 mm — the shallower the taper, the further away the apex.How-toHow to Find the Distance Between Two PointsUse the distance formula d = √((x₂−x₁)² + (y₂−y₁)²) to measure the straight-line distance between two points on a plane, with a worked example and the midpoint too.How-toHow to Calculate the Slope of a Line: Rise Over RunFind the slope of a line from two points with m = (y₂ − y₁) / (x₂ − x₁), and read what a positive, negative, zero, or undefined slope tells you.ExplainerThe Pythagorean Theorem ExplainedIn a right triangle, a² + b² = c². Here's what the formula means, a worked example, how to find any side, and where it's used in real life.How-toHow to Calculate VolumeVolume is the space inside a shape. Here's how to find it for boxes, cylinders and spheres, and why keeping your units consistent is the whole game.
Regular polygon perimeter calculator — OneKitly