Triangle Calculator

About Triangle Calculator

Calculate triangle perimeter and area from three sides.

How to Use

Calculate triangle perimeter and area from three sides. Enter the Side A, Side B, and Side C values and review the Perimeter, Area, and Status outputs after you calculate.

  1. Open the calculator : Use Triangle Calculator from the Math category.
  2. Check the inputs : Review the required values and any optional settings.
  3. Read the formula : Use the formula and notes below to understand how the result is produced.

Common Questions

What formula does the Triangle Calculator use?

Uses Heron formula when sides form a valid triangle.

Inputs

  • Side A
  • Side B
  • Side C

Outputs

  • Perimeter
  • Area
  • Status

Formula

Uses Heron formula when sides form a valid triangle.