Classifying Triangles Calculator

To classify a triangle by its sides, you need to check how many sides have equal lengths.

• Equilateral triangle – has three equal sides (and three equal angles);
• Isosceles triangle – has two equal sides; and
• Scalene triangle – has no equal sides.

There are three types of triangles based on their angles:

• If all of the triangle angles are less than 90°, then it's an acute triangle;
• If one of the angles measures more than 90°, it's an obtuse triangle; and
• If one of the angles is exactly 90°, then it's a right triangle.

Now you know that triangles can be classified by their sides or angles. A triangle can be equilateral, isosceles, or scalene, but also acute, obtuse, or right. When you try using our classifying triangles calculator, you will also find out that you can mix these names to give a more detailed description:

• Equilateral

🔎 To calculate all the parameters of this kind of triangle, go to equilateral triangle calculator.

• Acute scalene

• Obtuse scalene

• Right scalene

🔎 To calculate all the parameters of a scalene triangle, go to the scalene triangle calculator.

• Acute isosceles

• Obtuse isosceles

• Right isosceles

🔎 To calculate all the parameters of a isosceles triangle, go to the isosceles triangle calculator.

💡 Did you know that if you know the length of the sides of a triangle, you can also determine the size of its angles? However, it doesn't work the other way around. You can't find the sides of a triangle from its angles. Learn more in the triangle side calculator.

With our calculator, you can find out the type of your triangle based on your parameters. You can input:

• Three sides;
• Angle and two sides; or
• Two angles.

Based on that, the classifying triangles calculator will:

• Give you other parameters that it could determine about your triangle;
• Tell you the type of your triangle, and
• Show you an example of what your type of triangle might look like.