Scalene Triangle Calculator

Instantly compute side lengths, angles, area, heights, inradius, circumradius, and more. Visualize your triangle and verify the triangle inequality.

Triangle inequality: a + b > c, a + c > b, b + c > a. All sides positive.
5,6,7
7,8,9
4,5,6
8,15,17
13,14,15
3.5,4.2,5.8

What is a Scalene Triangle?

A scalene triangle is a triangle with three sides of different lengths and three angles of different measures. It is the most general type of triangle — no equal sides, no equal angles. All triangles that are not equilateral or isosceles are scalene.

✨ Key Formulas for SSS Scalene Triangle
  • Area (Heron): √[s(s-a)(s-b)(s-c)], s = (a+b+c)/2
  • Angles (Law of Cosines): cos(A) = (b² + c² - a²)/(2bc)
  • Circumradius R: (abc) / (4·Area)
  • Inradius r: Area / s
  • Altitude hₐ: 2·Area / a
  • Median mₐ: ½√(2b²+2c²-a²)

Why use a Scalene Triangle Calculator?

Manually applying Heron’s formula and the law of cosines is time-consuming and error-prone. Our calculator instantly returns all missing dimensions, validates triangle inequality, and draws the triangle. Perfect for students, architects, engineers, and math enthusiasts.

Frequently Asked Questions

Absolutely. If the three sides satisfy the Pythagorean theorem, the calculator will show a perfect 90° angle. It still is scalene unless two sides are equal.

We check the triangle inequality. If violated, a clear error message appears and no results are shown. Ensure each side is positive and sum of any two > third.

If two or three sides are equal, the triangle is isosceles or equilateral. Our badge will indicate that. The calculations remain correct, but the name 'scalene' implies all sides distinct.

We place side c horizontally, then use law of cosines to position the third vertex. Scaling adapts to fit the canvas. It's a schematic representation, not exact to scale but proportional.