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Free Triangle Calculator
Calculate sides, angles, area, and perimeter of any triangle.
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CalculateQuick Answer
Triangle: angles sum to 180°. Area = ½×base×height or use Heron's formula. Law of sines: a/sinA = b/sinB. Law of cosines: c² = a² + b² - 2ab×cosC.
Key Facts about Triangle Calculator:
- Angles sum to 180°
- Area = ½ × base × height
- Law of sines: a/sinA = b/sinB
- Law of cosines for any triangle
- Heron's formula for area from sides
Why Use Our Triangle Calculator?
Triangle tools:
📐
Any Triangle
Right, acute, obtuse.
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All Properties
Sides, angles, area.
📈
Multiple Methods
Different inputs.
🔢
Step-by-Step
Shows work.
⚡
Instant
Quick results.
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Private
Data stays secure.
How to Triangle Calculator in 3 Easy Steps
Solve triangle:
1
Enter Known Values
Sides and/or angles.
2
Calculate
Solve the triangle.
3
View All Values
See complete solution.
Why Use Our Calculator?
Any triangle type
Multiple input methods
Complete solution
Shows formulas
📐
Triangles
Complete triangle solver
Frequently Asked Questions
Everything you need to know about our triangle calculator
What is law of sines?
a/sin(A) = b/sin(B) = c/sin(C).
a/sin(A) = b/sin(B) = c/sin(C). Relates sides to opposite angles.
Still have questions? Try the tool yourself!
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