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Triangle

Triangle Calculator

Online Triangle Calculator for Sides, Angles, and Area

This Triangle Calculator determines a triangle’s properties from three known side lengths. You can enter the lengths for side A, side B, and side C to find the internal angles, area, perimeter, and type of triangle. The tool uses the law of cosines and Heron’s formula to provide accurate geometric solutions without manual calculations.

  • Side-Side-Side (SSS) Input: Solves any triangle when the lengths of all three sides are known.
  • Angle Calculation: Automatically computes the three internal angles of the triangle in degrees.
  • Area and Perimeter: Instantly calculates the area and the perimeter of the triangle.
  • Triangle Identification: Determines if the triangle is equilateral, isosceles, scalene, or a right triangle based on your inputs.

How to Use the Triangle Calculator

  1. Enter the length of Side A into the first input box.
  2. Provide the length of Side B in the second input box.
  3. Type the length of Side C into the final input box.
  4. Click the Calculate button to get the triangle’s complete properties.