Area of a Triangle Calculator FAQs
How do you find the area of a triangle from base and height?
Use the formula A = b × h / 2, where b is the base and h is the perpendicular height.
How do you find the area of a triangle from 3 sides?
Use Heron's formula: first calculate the semiperimeter s = (a + b + c) / 2, then calculate A = sqrt(s(s-a)(s-b)(s-c)).
How do you find triangle area from two sides and the angle?
Use A = ab sin(γ) / 2, where a and b are the known sides and γ is the angle between them.
How do you find the area of a triangle from one side and two angles?
If one side and the other two angles are known, the area can be found with A = a² sin(β) sin(γ) / (2 sin(β + γ)), using the known side and the two known angles.
How do you find triangle area from the circumradius?
If all three sides and the circumradius are known, use A = abc / 4R, where R is the circumradius.
How do you find triangle area from the inradius?
If the semiperimeter s and the inradius r are known, use A = sr.
Can this calculator find a missing triangle value from the area?
Yes. In the base and height mode you can solve for the base or the height. In the two sides and angle mode you can solve for a missing side and, in the principal-angle form, the angle. The calculator also supports reverse solving for the known side in the one side and two angles mode, for the circumradius in the three sides and circumradius mode, and for the semiperimeter or inradius in the semiperimeter and inradius mode.
