Isosceles Triangle Angles Calculator

Calculate Isosceles Triangle Angles

Enter the known angle's value.

Instantly calculate the angles of any isosceles triangle! Whether you know the vertex angle or a base angle, our free online tool provides accurate results, simplifying complex geometry problems for students and professionals. Discover the properties and solve your triangle challenges easily.

Formula:

An isosceles triangle has two equal sides and two equal base angles. The sum of all angles in a triangle is 180°.

  • If Vertex Angle (V) is known: Base Angle (B) = (180° - V) / 2
  • If Base Angle (B) is known: Vertex Angle (V) = 180° - 2B

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