Triangle Calculator - SSS, SAS, ASA and more

SSS (Side-Side-Side)

Enter all three sides of the triangle.

Side a

Side b

Side c

SAS (Side-Angle-Side)

Enter two sides and the included angle.

Side a

Angle B (degrees)

Side c

ASA (Angle-Side-Angle)

Enter two angles and the included side.

Angle A (degrees)

Side b

Angle C (degrees)

Base & Height

Enter the base and height of the triangle.

Base

Height

Right Triangle

Enter any two elements of a right triangle.

Side a (adjacent)

Side b (opposite)

Hypotenuse c

Angle A (degrees)

Angle B (degrees)

AAS (Angle-Angle-Side)

Enter two angles and a non-included side.

Angle A (degrees)

Angle B (degrees)

Side a

Results

Triangle Properties

Area:
Perimeter:
Semi-perimeter:

Sides

Side a:
Side b:
Side c:

Angles

Angle A:
Angle B:
Angle C:

Advanced Properties

Inradius:
Circumradius:
Height from A:
Height from B:
Height from C:

Visualization

Calculation Steps

Formulas Used

Triangle Information

Triangle Inequality Theorem: The sum of any two sides must be greater than the third side.

Triangle Types:

Equilateral: All sides equal
Isosceles: Two sides equal
Scalene: All sides different
Right: One 90° angle

Common Formulas:

Area: ½ × base × height
Heron's: √[s(s-a)(s-b)(s-c)]
Law of Cosines: c² = a² + b² - 2ab cos(C)
Law of Sines: a/sin(A) = b/sin(B) = c/sin(C)