Triangle Calculator

Please provide 3 values including at least one side to the following 6 fields, and click the "Calculate" button. When radians are selected as the angle unit, it can take values such as pi/2, pi/4, etc.

Angle Unit:
A B C a b c
side b
side a
A
side b
side a
B
side c
angle B
C
angle C
angle A

Equilateral Triangle

Sides

Side a = 1.00
Side b = 1.00
Side c = 1.00

Angles

∠A = 60.00°
∠B = 60.00°
∠C = 60.00°
In radians = 1.0472 rad = π/3

Basic Measurements

Area = 0.43301
Perimeter p = 3.00
Semiperimeter s = 1.50

Heights

ha = 0.86603
hb = 0.86603
hc = 0.86603

Medians

ma = 0.86603
mb = 0.86603
mc = 0.86603

Radii

Inradius r = 0.28868
Circumradius R = 0.57735

Vertex Coordinates

A = [0, 0]
B = [1, 0]
C = [0.5, 0.86603]

Centers

Centroid = [0.5, 0.28868]
Incenter = [0.5, 0.28868]
Circumcenter = [0.5, 0.28868]

A triangle is a polygon that has three vertices. A vertex is a point where two or more curves, lines, or edges meet; in the case of a triangle, the three vertices are joined by three line segments called edges. A triangle is usually referred to by its vertices. Hence, a triangle with vertices a, b, and c is typically denoted as △abc. Furthermore, triangles tend to be described based on the length of their sides, as well as their internal angles. For example, a triangle in which all three sides have equal lengths is called an equilateral triangle while a triangle in which two sides have equal lengths is called isosceles. When none of the sides of a triangle have equal lengths, it is referred to as scalene, as depicted below.

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