Triangle Calculator
📜 History
📘 How to Use
2️⃣ Choose which angle you want trigonometry values for.
3️⃣ Tap Calculate to see angles, sin/cos/tan, and the drawn triangle.
4️⃣ View the angle values directly on the triangle diagram.
5️⃣ Previous calculations are saved automatically and can be exported as a PDF.
Advanced Triangle Calculator
This free triangle calculator helps you solve any triangle using only three sides. It automatically calculates all angles, provides trigonometric values (sin, cos, tan), draws a visual diagram, and shows step-by-step explanations.
Whether you’re a student, engineer, or working with geometry in real-world applications, this tool simplifies complex triangle calculations instantly.
Triangle Solver Tool
History
What Is a Triangle Calculator?
A triangle calculator is a mathematical tool used to determine unknown sides and angles of a triangle. By entering known values, the calculator applies geometric formulas such as the Law of Cosines and Law of Sines to compute missing values.
This advanced version goes beyond basic calculations by including trigonometry, visual diagrams, and step-by-step explanations to improve understanding.
How to Use This Triangle Calculator
Using this calculator is simple:
1. Enter the three side lengths (A, B, and C).
2. Select the angle for trigonometric calculations.
3. Click “Calculate Triangle”.
4. View angles, trigonometric values, and the triangle diagram.
5. Export your results if needed.
Triangle Formulas Explained
Law of Cosines
The Law of Cosines is used to calculate angles when all three sides are known:
cos(A) = (b² + c² − a²) / (2bc)
This formula allows us to calculate angle A, and similarly for angles B and C.
Trigonometric Functions
Once angles are known, we can calculate:
sin(θ) – ratio of opposite to hypotenuse
cos(θ) – ratio of adjacent to hypotenuse
tan(θ) – ratio of opposite to adjacent
Types of Triangles You Can Solve
This calculator works for all triangle types:
• Equilateral triangles (all sides equal)
• Isosceles triangles (two sides equal)
• Scalene triangles (all sides different)
• Acute, obtuse, and right triangles
Why Use This Triangle Calculator?
Unlike basic calculators, this tool provides:
• Instant angle calculations
• Trigonometry values
• Visual triangle diagrams
• Step-by-step explanations
• Calculation history with export feature
Real-Life Applications
Triangle calculations are used in many real-world fields:
• Construction and architecture
• Engineering and design
• Navigation and GPS systems
• Physics and mechanics
• Computer graphics and game development
Frequently Asked Questions
Can I solve any triangle?
Yes, as long as you provide three valid sides that form a triangle.
What if my triangle is invalid?
The calculator checks the triangle inequality rule and will alert you if the triangle cannot exist.
Is this calculator free?
Yes, it is completely free with no limits.