# Triangle Calculator

> Solve a general triangle from three known values, including at least one side, and calculate sides, angles, area, radii, and medians.

Page: https://askcalculators.com/calculator/triangle-calculator/
Definition: https://askcalculators.com/calculator/triangle-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/triangle-calculator/schema.json
Version: 2.0.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/calculator/triangle-calculator/?sideA=3&sideB=4&sideC=5&angleUnit=degrees

## Inputs
- sideA: Side a; type=number; optional; default=3; min=0.000001
- angleA: Angle A; type=number; optional; min=0.000001
- sideB: Side b; type=number; optional; default=4; min=0.000001
- angleB: Angle B; type=number; optional; min=0.000001
- sideC: Side c; type=number; optional; default=5; min=0.000001
- angleC: Angle C; type=number; optional; min=0.000001
- angleUnit: Angle unit; type=select; required; default=degrees; values=degrees|radians

## Outputs
- sideAResult: Side a; format=number; primary
- sideBResult: Side b; format=number
- sideCResult: Side c; format=number
- angleAResult: Angle A; format=number
- angleBResult: Angle B; format=number
- angleCResult: Angle C; format=number
- area: Area; format=number
- perimeter: Perimeter; format=number
- inradius: Inradius; format=number
- circumradius: Circumradius; format=number
- medianA: Median to side a; format=number
- medianB: Median to side b; format=number
- medianC: Median to side c; format=number
- triangleType: Triangle type; format=text
- solutionCount: Possible solutions; format=integer

## Formula
Use the law of cosines for SSS/SAS, the law of sines for ASA/AAS/SSA, and Heron’s formula K=√[s(s−a)(s−b)(s−c)].

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.