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Calcimator

Triangle Calculator

Calculate area, angles, heights, perimeter, inradius, and circumradius of any triangle from three sides.

Inputs

Results

Area

17.32

Perimeter20
Triangle TypeScalene Acute
Angle A38.21°
Angle B60°
Angle C81.79°
Height from A6.93
Inradius1.73
Circumradius4.04

Area

17.32

How to Use This Calculator
  1. Start by filling in the input fields below. Results update instantly as you type, so you can experiment with different values to see how they affect the outcome.
  2. Side a — Length of side A. Accepts values from 0.1 to 10,000 (default: 5).
  3. Side b — Length of side B. Accepts values from 0.1 to 10,000 (default: 7).
  4. Side c — Length of side C. Accepts values from 0.1 to 10,000 (default: 8).
  5. Once all inputs are set, review your results in the Results panel. Here's what each output means:
  6. Area — shown as a numeric value. This is the primary result of this calculator.
  7. Perimeter — shown as a numeric value.
  8. Triangle Type — your calculated result.
  9. Angle A — shown as a numeric value.
  10. Angle B — shown as a numeric value.
  11. Angle C — shown as a numeric value.
  12. Height from A — shown as a numeric value.
  13. Inradius — shown as a numeric value.
  14. Circumradius — shown as a numeric value.
  15. Scroll down to explore 2 charts (Angles, Sides) for a visual breakdown of the data.
  16. Explore the related calculators below if you need deeper analysis or want to approach this topic from a different angle.
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Formula

A = √(s(s-a)(s-b)(s-c)) where s = (a+b+c)/2

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