Trapezoid Calculator

Calculate area and perimeter of trapezoids with detailed analysis

Trapezoid Measurements
Enter the dimensions of your trapezoid
Example Trapezoids
Click to load common trapezoid examples
Area + Perimeter

Regular Trapezoid

Isosceles trapezoid with equal sides

Bases: 10 × 6
Height: 4
Sides: 5 × 5
Area + Perimeter

Roof Truss

Common roof truss shape

Bases: 12 × 8
Height: 3
Sides: 4 × 4
Area Only

Garden Bed

Trapezoidal garden bed area calculation

Bases: 15 × 10
Height: 5
Area + Perimeter

Bridge Support

Bridge support structure

Bases: 20 × 14
Height: 8
Sides: 10 × 10
Area Only

Swimming Pool

Trapezoidal swimming pool surface area

Bases: 25 × 15
Height: 12
Trapezoid Formulas
Mathematical formulas used in calculations

Area

A = (b₁ + b₂) × h ÷ 2

Area of trapezoid using parallel bases and height

Variables:
AArea
b₁First parallel base
b₂Second parallel base
hHeight (perpendicular distance between bases)

Perimeter

P = b₁ + b₂ + s₁ + s₂

Perimeter using all four sides

Variables:
PPerimeter
b₁First parallel base
b₂Second parallel base
s₁First non-parallel side
s₂Second non-parallel side

Median (Midsegment)

m = (b₁ + b₂) ÷ 2

Length of the median (line connecting midpoints of non-parallel sides)

Variables:
mMedian length
b₁First parallel base
b₂Second parallel base