Triangle Calculator

Calculate triangle properties by entering any three values (at least one side). Supports both degree and radian angles.

Understanding Triangles

A triangle is a three-sided polygon with three vertices and three angles. The sum of all internal angles in a triangle is always 180 degrees (π radians).

Types of Triangles

  • Equilateral Triangle: All sides and angles are equal (60° each)
  • Isosceles Triangle: Two sides and two angles are equal
  • Scalene Triangle: All sides and angles are different
  • Right Triangle: Has one 90° angle

Key Triangle Properties

  • Area = ½ × base × height
  • Perimeter = sum of all sides
  • The longest side is opposite to the largest angle
  • The sum of any two sides must be greater than the third side
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