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Regular Polygon Area Calculator - Geometry Calculator | Toolivaa

Regular Polygon Area Calculator

Calculate Polygon Area

Calculate area of any regular polygon from side length, apothem, radius, or number of sides. Visualize polygon shape and properties.

A = (n × s²) / (4 × tan(π/n))
Side Length
Apothem
Circumradius

From Side Length

Triangle
Square
Pentagon
Hexagon
Octagon
Decagon

Regular Hexagon

s = 10, n = 6
Area = 259.81

Square

s = 10, n = 4
Area = 100.00

Regular Pentagon

s = 10, n = 5
Area = 172.05
Regular polygons have equal sides and equal interior angles.

Polygon Area Result

259.81 square units

Polygon Visualization

Vertices | Center | Apothem
6
Sides (n)
10.00
Side Length (s)
8.66
Apothem (a)
10.00
Circumradius (R)

Formula Used:

A = (n × s²) / (4 × tan(π/n))

Where: A = area, n = number of sides, s = side length

Interior Angle

120.00°

Each interior angle = 180 × (n-2) / n

Sum of interior angles = 180 × (n-2)

Step-by-Step Calculation:

1. Given: n = 6, s = 10
2. Calculate π/n = π/6 ≈ 0.5236
3. Compute tan(π/n) = tan(0.5236) ≈ 0.5774
4. Square side length: s² = 10² = 100
5. Multiply: n × s² = 6 × 100 = 600
6. Divide: 600 / (4 × 0.5774) = 600 / 2.3094 ≈ 259.81
7. Result: Area = 259.81 square units

Symmetry Properties

Dih₆

Rotational symmetry: 6-fold

Reflection symmetry: 6 lines

Dihedral group: Dih6

Perimeter
60.00
Inradius
8.66
Central Angle
60.00°
Area Ratio
0.83

Shape Name: Regular Hexagon

Area Approximation: ≈ 260 square units

Applications: Architecture, engineering, computer graphics, nature patterns

A regular hexagon with side length 10 units has an area of 259.81 square units. The apothem (distance from center to side midpoint) is 8.66 units, and the circumradius (distance from center to vertex) is 10 units.

What is a Regular Polygon?

A regular polygon is a polygon that is both equilateral (all sides equal) and equiangular (all angles equal). Regular polygons are highly symmetric shapes found throughout mathematics, nature, and human design. As the number of sides increases, a regular polygon approaches a circle.

Regular Polygon Formulas

From Side Length

A = (n × s²) / (4 × tan(π/n))

Most common formula

Requires side length

From Apothem

A = ½ × n × s × a

Using apothem length

Half perimeter × apothem

From Circumradius

A = ½ × n × R² × sin(2π/n)

Using circumradius

Circle-related formula

Perimeter

P = n × s

Total boundary length

Sum of all sides

Common Regular Polygons

Triangle
n = 3
A = (√3/4)s²
Equilateral
Square
n = 4
A = s²
Quadrilateral
Pentagon
n = 5
A = (1/4)√(5(5+2√5))s²
Golden ratio
Hexagon
n = 6
A = (3√3/2)s²
Honeycomb
Octagon
n = 8
A = 2(1+√2)s²
Stop sign

Polygon Area Formulas

1. From Side Length (Standard Formula)

A = (n × s²) / (4 × tan(π/n))

Where:

  • A = area of regular polygon
  • n = number of sides
  • s = side length
  • π = mathematical constant (≈ 3.14159)

2. From Apothem (Simpler Formula)

A = ½ × P × a = ½ × (n × s) × a

Where:

  • A = area of regular polygon
  • P = perimeter = n × s
  • a = apothem (distance from center to side midpoint)
  • n = number of sides
  • s = side length

3. From Circumradius (Circle Relationship)

A = ½ × n × R² × sin(2π/n)

Where:

  • A = area of regular polygon
  • n = number of sides
  • R = circumradius (distance from center to vertex)
  • 2π/n = central angle in radians

Common Polygon Area Calculations

PolygonSides (n)Side Length (s)AreaFormula Used
Equilateral Triangle31043.30A = (√3/4)s²
Square410100.00A = s²
Regular Pentagon510172.05A = (1/4)√(5(5+2√5))s²
Regular Hexagon610259.81A = (3√3/2)s²

Polygon Properties and Relationships

PropertyFormulaDescriptionExample (n=6)
Interior Angle180° × (n-2)/nAngle between adjacent sides120°
Central Angle360°/nAngle at center between vertices60°
Apothems / (2 × tan(π/n))Distance from center to side8.66 (s=10)
Circumradiuss / (2 × sin(π/n))Distance from center to vertex10.00 (s=10)

Real-World Applications

Architecture & Construction

  • Structural design: Hexagonal and octagonal floor plans for optimal space usage
  • Tile patterns: Regular polygons in tiling (triangles, squares, hexagons)
  • Dome construction: Geodesic domes using triangular polygons
  • Window design: Octagonal and hexagonal windows in architecture

Nature & Biology

  • Honeycomb structure: Hexagonal cells for optimal space efficiency
  • Crystal formations: Regular polygonal patterns in mineral crystals
  • Cell structures: Polygonal shapes in biological cell arrangements
  • Snowflakes: Hexagonal symmetry in ice crystal formation

Engineering & Design

  • Bolt heads: Hexagonal and octagonal shapes for tools
  • Gear design: Regular polygonal teeth for smooth rotation
  • Computer graphics: Polygonal modeling for 3D objects
  • Packaging design: Optimal space utilization with polygonal shapes

Mathematics & Education

  • Geometry education: Fundamental shapes for teaching mathematics
  • Tessellation studies: Regular polygons in plane filling patterns
  • Symmetry groups: Dihedral groups in abstract algebra
  • Trigonometry: Applications in trigonometric calculations

Step-by-Step Calculation Examples

Example 1: Regular Hexagon with side = 10

  1. Number of sides: n = 6
  2. Side length: s = 10
  3. Calculate π/n: π/6 ≈ 0.5236 radians
  4. Compute tangent: tan(π/6) = tan(30°) = 1/√3 ≈ 0.5774
  5. Square side length: s² = 10² = 100
  6. Multiply: n × s² = 6 × 100 = 600
  7. Divide denominator: 4 × tan(π/n) = 4 × 0.5774 = 2.3094
  8. Final calculation: 600 / 2.3094 ≈ 259.81
  9. Result: Area ≈ 259.81 square units

Example 2: Square with side = 10 (Simplified)

  1. Number of sides: n = 4
  2. Side length: s = 10
  3. Use simplified formula for square: A = s²
  4. Calculate: 10² = 100
  5. Result: Area = 100 square units
  6. Verification using general formula: tan(π/4) = tan(45°) = 1, A = (4 × 100) / (4 × 1) = 400 / 4 = 100

Related Calculators

Frequently Asked Questions (FAQs)

Q: What's the difference between regular and irregular polygons?

A: Regular polygons have all sides equal and all angles equal (e.g., equilateral triangle, square). Irregular polygons have sides and/or angles of different lengths/measures. Regular polygons are symmetric, while irregular polygons lack symmetry.

Q: How do I find the apothem if I only know the side length?

A: For a regular polygon with n sides and side length s, the apothem is: a = s / (2 × tan(π/n)). For example, for a regular hexagon (n=6): a = s / (2 × tan(30°)) = s / (2 × 0.5774) ≈ s / 1.1547.

Q: What happens to the area as the number of sides increases?

A: As n → ∞, the regular polygon approaches a circle. The area approaches πR² where R is the circumradius. For a fixed circumradius, area increases with n and approaches the circle area. For a fixed side length, area increases dramatically with n.

Q: Can all regular polygons tessellate (tile the plane)?

A: Only three regular polygons can tessellate by themselves: equilateral triangles (n=3), squares (n=4), and regular hexagons (n=6). Other regular polygons cannot tile the plane alone because their interior angles don't divide 360° evenly.

Accurately calculate polygon areas with Toolivaa's free Regular Polygon Area Calculator, and explore more geometric tools in our Geometry Calculators collection.

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