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  1. Home
  2. Math Calculators
  3. Parallelogram Calculator

Parallelogram Calculator

Calculate parallelogram area, perimeter, diagonals, angles, and height. Enter sides and angles to get all measurements with interactive visualization.

Formula:A = base × height | P = 2(a + b)

Parallelogram Properties

Area

60.6218 cm^2

Perimeter34.0000 cm
Height6.0622 cm
Diagonal 18.8882 cm
Diagonal 214.7986 cm

Parallelogram Input

deg

Try Common Parallelograms

Quick-start with common scenarios

Parallelogram Visualization

a = 10.00 cmb = 7.0060.0degh = 6.06d1 = 8.89

Complete Results

Sides

Side a

10.0000 cm

Side b

7.0000 cm

Angles

Angle A (and C)

60.00deg

Angle B (and D)

120.00deg

Measurements

Area

60.6218 cm^2

A = base x height

Perimeter

34.0000 cm

P = 2(a + b)

Height

6.0622 cm

h = b x sin(A)

Diagonals

Diagonal 1

8.8882 cm

Diagonal 2

14.7986 cm

Check: d1^2 + d2^2 = 298.0000, 2(a^2 + b^2) = 298.0000

Parallelogram Formulas

Area Formulas

  • A = base x height
  • A = a x b x sin(angle)
  • A = (1/2) x d1 x d2 x sin(theta)

Diagonal Formulas

  • d1 = sqrt(a^2+b^2-2ab cos A)
  • d2 = sqrt(a^2+b^2+2ab cos A)
  • d1^2 + d2^2 = 2(a^2+b^2)

Tip: Consecutive angles in a parallelogram always sum to 180 degrees. If you know one angle, the adjacent angle is 180 degrees minus that angle.

Special Cases

Rectangle

All angles = 90 degrees. Diagonals are equal.

Rhombus

All sides equal. Diagonals perpendicular.

Square

Rectangle + Rhombus. All sides equal, all angles 90 degrees.

Parallelogram Properties

Area

60.6218 cm^2

Perimeter34.0000 cm
Height6.0622 cm

?How to Calculate Parallelogram Properties

Parallelogram formulas: Area = base x height = a x b x sin(angle). Perimeter = 2(a + b). The diagonals bisect each other. Opposite angles are equal and consecutive angles are supplementary (sum to 180 degrees). Both diagonals can be calculated using the law of cosines.

What is a Parallelogram?

A parallelogram is a quadrilateral with two pairs of parallel sides. Opposite sides are equal in length, opposite angles are equal, and consecutive angles are supplementary (add up to 180 degrees). The diagonals of a parallelogram bisect each other. Special cases include rectangles (with right angles), rhombi (with equal sides), and squares (with both).

Key Facts About Parallelograms

  • Area = base x height = a x h
  • Area = a x b x sin(angle) using sides and included angle
  • Perimeter = 2(a + b) = 2a + 2b
  • Opposite sides are equal and parallel
  • Opposite angles are equal
  • Consecutive angles are supplementary (sum to 180 degrees)
  • Diagonals bisect each other (but are not equal unless rectangle)
  • d1^2 + d2^2 = 2(a^2 + b^2) - parallelogram law
  • A rectangle is a special parallelogram with 90 degree angles
  • A rhombus is a special parallelogram with all sides equal

Quick Answer

Parallelogram formulas: Area = base x height = a x b x sin(angle). Perimeter = 2(a + b). The diagonals bisect each other. Opposite angles are equal and consecutive angles are supplementary (sum to 180 degrees). Both diagonals can be calculated using the law of cosines.

Parallelogram Practice Problems

Test your skills with practice problems

Practice with 4 problems to test your understanding.

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Frequently Asked Questions

The area of a parallelogram can be calculated as: Area = base x height, or Area = a x b x sin(angle), where a and b are adjacent sides and angle is the included angle between them.

Area = base x height, or Area = a x b x sin(angle).

Using the law of cosines: d1 = sqrt(a^2 + b^2 - 2ab cos(A)) and d2 = sqrt(a^2 + b^2 + 2ab cos(A)), where A is one of the angles. The diagonals bisect each other but are generally not equal.

Use law of cosines with sides and angle.

Opposite angles are equal (angle A = angle C, angle B = angle D). Consecutive angles are supplementary, meaning they add up to 180 degrees (angle A + angle B = 180).

Opposite angles are equal; consecutive angles sum to 180 degrees.

A parallelogram is a rectangle when all four angles are right angles (90 degrees). In this case, the diagonals are equal in length.

When all angles are 90 degrees.

A parallelogram is a rhombus when all four sides are equal in length. In a rhombus, the diagonals bisect each other at right angles.

When all four sides are equal.

The parallelogram law states that the sum of the squares of the diagonals equals twice the sum of the squares of the sides: d1^2 + d2^2 = 2(a^2 + b^2).

d1^2 + d2^2 = 2(a^2 + b^2).

Last updated: 2025-01-15

Parallelogram Properties

Area

60.6218 cm^2

Perimeter34.0000 cm
Height6.0622 cm
Diagonal 18.8882 cm
Diagonal 214.7986 cm