Triangle Calculator

Length of Side a:
Length of Side b:
Length of Side c:
Angle A:
Angle B:
Angle C:

Area:
Perimeter:
Height of a:
Height of b:
Height of c:
Angle Bisector of a:
Angle Bisector of b:
Angle Bisector of c:
Median of a:
Median of b:
Median of c:

Note: Calculation can be based on any 3 items above. If no results after click "Calculate" button, then the data provided is impossible to shape a triangle.

Calculation can be based on the coordinates of the three points of the triangle:

X
Y
A :
B :
C :

Note: If no results after filling in all coordinates, then the data provided is impossible to shape a triangle.

Triangle has three sides and three angles. The sum length of any two sides is longer than the length of the other side. All angles of a triangle always add up to 180 ̊C. Triangle has three types based on its three angles, including obtuse (1 angle > 90 ̊C), right (1 angle = 90 ̊C) and acute (no angle > 90 ̊C). It can be divided into three types based on three sides too, including scalene (no equal sides), equilateral (all sides equal) and isoscele (2 sides equal). Triangle Formulas

• Law of Cosines
a2 = b2 + c2 - 2 × b × c × CosA;
b2 = a2 + c2 - 2 × a × c × CosB;
c2 = b2 + a2 - 2 × b × a × CosC;

• Area
a × b × Sin(C) / 2 or
c × b × Sin(A) / 2 or
a × c × Sin(B) / 2

• Angle Bisector of Side a
2 × b × c × Cos(A/2) / (b + c)

• Angle Bisector of Side b
2 × a × c × Cos(B/2) / (a + c)

• Angle Bisector of Side c
2 × a × b × Cos(C/2) / (a + b)

• Median of Side a ( ma )
ma2 = (2 * b2 + 2 * c2 - a2) / 4

• Median of Side b ( mb )
mb2 = (2 * a2 + 2 * c2 - b2) / 4

• Median of Side c ( mc )
mc2 = (2 * a2 + 2 * b2 - c2) / 4

a / ( 2 * sin (A)) or
b / ( 2 * sin (B)) or
c / ( 2 * sin (C))

a × Sin(C/2) × Sin(B/2) / Cos (A/2) or
b × Sin(A/2) × Sin(C/2) / Cos (B/2) or
c × Sin(A/2) × Sin(B/2) / Cos (C/2)

Triangle Types

All three angles of a triangle always add up to 180 ̊C. Triangle has three types based on its three angles.   Obtuse Trianglehas an angle > 90 ̊C. Right Trianglehas an angle = 90 ̊C. Acute Triangleall angles < 90 ̊C.

Triangle has three types based on the equality of its three sides.   Equilateral Triangleall sides are equal, all angles are 60 ̊C. Isosceles Triangletwo equal sides. Scalene Triangleno equal sides and angles. Home Popular Baby Names by Surname Unit Conversions Biology Geometry, Trigonometry Physics Chemistry Mathmatics Medical Algebra Statistics Nutrition of Foods, Health R Programming Tutorials Javascript Tutorials Time Zone Converter Top Visited Websites Directory Vocabulary and Phrases