Triangle Perimeter Calculator
Result
Perimeter12
Semi-Perimeter6
Area (Heron's)6
Triangle TypeRight triangle detected (a²+b²=c²)
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Triangle Perimeter Calculator — free online calculator.
Formula
Perimeter = a+b+c; s = (a+b+c)/2; Area = √(s(s−a)(s−b)(s−c))
- Triangle Perimeter Calculator calculates its result from C, A, B, S S A S B. It uses the formula Perimeter = a+b+c; s = (a+b+c)/2; Area = √(s(s−a)(s−b)(s−c)). Change any input to recalculate the result instantly.
- The main inputs are Side a, Side b, Side c. Enter them in the units and format shown in the calculator.
- Keep comparable quantities in compatible units whenever the formula combines or compares them.
- Changing any input above recalculates the result with the same calculation engine used by this page.
Example: Triangle Perimeter
Inputs
- Side a: 3
- Side b: 4
- Side c: 5
Using C = 2, A = 3, B = 4, S S A S B = 5, the calculated result is 3.5355339059.
Sample result: Calculating…
Frequently asked questions
What does the Triangle Perimeter calculate?
Triangle Perimeter Calculator — free online calculator.
Which values should I enter?
Enter Side a, Side b, Side c using the units and format shown beside each field.
What formula does this calculator use?
The calculator uses the following relationship: Perimeter = a+b+c; s = (a+b+c)/2; Area = √(s(s−a)(s−b)(s−c)).
Why might my result differ from another source?
Results can differ when another source uses different units, rounding rules, conventions or assumptions. Compare the inputs and definitions before comparing results.
Does the result update automatically?
Yes. Changing an input updates the result using the same calculation engine shown on this page.