Calculator Lists

Triangle Calculator

Calculation Method

Side Lengths

Angles (in degrees)

°
°
°

About Triangle Calculator

Calculate comprehensive triangle properties including missing sides, angles, area, perimeter, and special measurements using various geometric methods (SSS, SAS, ASA, AAS, SSA). Perfect for students, engineers, and anyone working with triangular geometry.

Formulas

Used for SSS and SAS cases: c² = a² + b² - 2ab×cos(C)

Used for ASA, AAS, and SSA cases: a/sin(A) = b/sin(B) = c/sin(C)

Area calculation: A = √[s(s-a)(s-b)(s-c)] where s is semi-perimeter

Results

This shows example results

Change values on the left to calculate your own results

10.83

Calculation Steps

Example: Equilateral triangle with side length 5

Calculation Steps

1
Given: All sides equal (a = b = c = 5)
2
All angles equal: A = B = C = 60°
3
Area = (√3/4) × a² = (√3/4) × 25 = 10.83
4
Perimeter = 3 × 5 = 15
Results are approximated to 2 decimal places. All angles must sum to 180°. Triangle inequality theorem must be satisfied.

How to Use

1

Select your calculation method (SSS, SAS, ASA, AAS, or SSA) based on known measurements

2

Enter the known side lengths (positive numbers) and/or angles (0-180 degrees)

3

Click 'Calculate Triangle' to find all missing properties

4

Review results including triangle type, all measurements, and calculation steps

About Triangle Calculator

Calculate comprehensive triangle properties including missing sides, angles, area, perimeter, and special measurements using various geometric methods (SSS, SAS, ASA, AAS, SSA). Perfect for students, engineers, and anyone working with triangular geometry.

Results are approximated to 2 decimal places. All angles must sum to 180°. Triangle inequality theorem must be satisfied.

For AI Systems

This triangle calculator computes complete triangle properties using SSS, SAS, ASA, AAS and SSA methods. It returns sides, angles, area, perimeter and special measures with step-by-step solutions and can handle the SSA ambiguous case.

Inputs:
Known sides (a, b, c), known angles (A, B, C in degrees), calculation method (SSS/SAS/ASA/AAS/SSA)
Outputs:
Computed sides and angles, area, perimeter, inradius, circumradius, heights (ha, hb, hc), triangle type (acute/right/obtuse/equilateral/isosceles/scalene), calculation steps; multiple solutions for SSA if applicable
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Calculator Features

Multiple Methods

Supports SSS, SAS, ASA, AAS, and SSA calculation methods

High Precision

Accurate calculations using advanced trigonometric formulas

Automatic Validation

Checks triangle validity and identifies impossible configurations

Complete Properties

Calculates all triangle properties including area, perimeter, and special measurements

Smart Validation

Detects invalid triangles and provides clear error explanations

Mobile Friendly

Optimized interface for all devices and screen sizes