What is Heron's formula?

Heron's formula calculates triangle area using all three sides: Area = √[s(s-a)(s-b)(s-c)], where s is the semi-perimeter (a+b+c)/2. It works for any triangle when you know all three sides.

How do I know if three sides can form a triangle?

Use the triangle inequality theorem: the sum of any two sides must be greater than the third side. Check that a+b>c, a+c>b, and b+c>a for sides a, b, and c.

What makes a triangle a right triangle?

A right triangle has one 90-degree angle. You can identify it using the Pythagorean theorem: if a² + b² = c² (where c is the longest side), then it's a right triangle.

How do I find triangle angles from sides?

Use the Law of Cosines: cos(C) = (a² + b² - c²)/(2ab). This gives you angle C opposite side c. Repeat for other angles or use the fact that angles sum to 180°.

Triangle Calculator – Area, Perimeter, Angles

Calculate triangle area, perimeter, angles, and sides using various methods. Supports right triangles, equilateral triangles, and general triangles with comprehensive calculations.

Triangle Calculator – Area, Perimeter, Angles

Calculate triangle area, perimeter, angles, and sides using various methods. Supports right triangles, equilateral triangles, and general triangles with comprehensive calculations.

Calculation Type*

Choose what you want to calculate

Side A (or Base)*

Length of first side or base

Side B

Length of second side

Side C

Length of third side

Height

Height perpendicular to base

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Math visualization will appear here

Triangle Calculations Made Easy

Triangles are fundamental shapes in geometry with many practical applications. Our calculator handles various triangle calculations including area, perimeter, and angle measurements using different input methods.

Triangle Area Formulas

Different methods to calculate triangle area:

Base and Height: Area = ½ × base × height
Three Sides (Heron's): Area = √[s(s-a)(s-b)(s-c)]
Two Sides and Angle: Area = ½ × a × b × sin(C)
Coordinates: Using coordinate geometry formulas

How to Use This Calculator

Follow these simple steps to get accurate results:

Enter your calculation type
Enter your side a (or base)
Enter your side b
Enter your side c
Enter your height
Click the "Calculate" button to see your results
Review the detailed breakdown and explanation

Why Use Our Triangle Calculator – Area, Perimeter, Angles?

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Instant, accurate calculations with professional formulas
Mobile-friendly design that works on any device
Privacy-focused - your data never leaves your browser
Educational content to help you understand the results

Frequently Asked Questions

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