Triangle Calculator

Calculate area, perimeter, and angles of triangles using base-height, three sides (Heron's formula), or two sides and included angle methods.

Calculator

Calculator Details

Enter your information to calculate results

Results
40.00
Area (square units)

Formula Used

Area = ½ × base × height
Area = ½ × 10 × 8 = 40.00

How It Works

Triangle calculations use different formulas depending on the known information:

Area Formulas:

  • Base & Height: Area = ½ × base × height
  • Heron's Formula: Area = √[s(s-a)(s-b)(s-c)] where s = (a+b+c)/2
  • Two Sides & Angle: Area = ½ × a × b × sin(C)

The calculator also determines triangle type (equilateral, isosceles, scalene) and whether it's a right triangle.

Examples

Right Triangle (3-4-5)

Sides: 3, 4, 5 units

Area: 6 square units

Perimeter: 12 units

Angles: 90°, 53.1°, 36.9°

Equilateral Triangle

All sides: 6 units

Area: 15.59 square units

Perimeter: 18 units

All angles: 60°

Compare

Triangle Types:

  • Equilateral: All sides equal, all angles 60°
  • Isosceles: Two sides equal, two angles equal
  • Scalene: All sides different, all angles different
  • Right: One angle is 90°

Applications:

  • Construction and architecture
  • Land surveying and mapping
  • Engineering and design
  • Navigation and trigonometry