Parallelogram Calculator
Calculate area, perimeter, height, diagonals, and angles of a parallelogram from known values.
Dimensions
Updates as you typeSolve from
What do you know? ?
Unit ?
Values
Base (b) ?
—
cm
Side (a) ?
—
cm
Height (h) ?
—
cm
Angle (θ) ?
—
°
Area (A) ?
—
cm²
Live diagram
Drag a vertexDrag a top vertex to reshape — inputs follow.
Formula
A
=
b × h
,
A
=
a × b × sin θ
,
P
=
2(a + b)
- A
- Area of the parallelogram
- b
- Base — the side you measure the height against
- a
- Adjacent side (the slanted one)
- h
- Perpendicular height from the base to the opposite side
- θ
- Interior angle between sides a and b
- P
- Perimeter (sum of all four sides)
- d1, d2
- Diagonals (from the law of cosines on the two triangles)
Worked example — your numbers
- Height h = a × sin θ = —
- Area A = b × h = —
- Perimeter P = 2(a + b) = —
- Diagonal d1 = √(b² + a² − 2·b·a·cos θ) = —
- Diagonal d2 = √(b² + a² + 2·b·a·cos θ) = —
- Sanity check d1² + d2² = 2(a² + b²) = —
A parallelogram is defined by two adjacent sides and the angle between them. When θ = 90° it becomes a rectangle; when all sides are equal it becomes a rhombus; when both hold, it’s a square. The diagonals are generally unequal — only at 90° do they match.