Triangle Calculator
Calculate all properties of a triangle — area, all angles, perimeter, and triangle type — from any 3 known values (sides, angles, or combinations). Free.
Triangle Calculator
toolznova.com • Free Calculator
How to Use
Calculate triangle in 3 steps.
Choose Known Values
Select SSS (3 sides), SAS (2 sides+angle), or ASA (2 angles+side).
Enter Values
Enter the three known measurements.
Get All Properties
Click Calculate for area, perimeter, all angles, and type.
Why ToolzNova?
Instant
Results in milliseconds.
Accurate
Precise formulas every time.
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No data sent anywhere.
Everywhere
Mobile, tablet, desktop.
Why Calculate Triangle Properties?
- Geometry: Core shape in mathematics with many applications.
- Construction: Triangular bracing is structurally strongest shape.
- Navigation: Triangulation used to determine positions.
- Surveying: Land surveying uses triangle calculations extensively.
- Physics: Force components and vector addition form triangles.
- Architecture: Roof trusses, pyramid structures, and bridge design.
Tips & Examples
- SSS: use Heron's formula and law of cosines for angles.
- SAS: use law of cosines to find third side, then angles.
- ASA: use law of sines — third angle = 180° - A - B.
- Sum of all angles = 180° always (Euclidean geometry).
- Equilateral: all sides equal. Isosceles: 2 sides equal. Scalene: all different.
- Heron's area: A = √(s(s-a)(s-b)(s-c)) where s = (a+b+c)/2.
Free Triangle Calculator Online
ToolzNova's free triangle calculator finds all triangle properties from SSS, SAS, or ASA inputs — area, perimeter, all three angles, and triangle classification (equilateral, isosceles, scalene, right, acute, obtuse).
Triangles are the simplest polygon and appear throughout mathematics, science, and engineering. Given any three pieces of information (sides and/or angles), all remaining properties can be calculated.
Triangle Formulas
Area (Heron's): A = √(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). All angles sum to 180°.