Area Calculator
Calculate Area of Any Shape

Professional area calculator for rectangles, squares, circles, triangles, and more. Get instant results with formulas explained. Perfect for students, architects, and DIY projects.

Used by professionals
Multiple shapes
Accurate formulas

Area Calculator

Calculate area and perimeter for various geometric shapes

Four-sided shape with opposite sides equal and all angles 90°

Quick Values

Calculation Results

Area, perimeter, and related measurements

Enter valid measurements to see the calculation results

Area Formulas Explained

Learn the essential formulas for calculating area of different shapes.

Rectangle Area
Area = Length x Width. The most common formula for rooms, plots, and rectangular objects. Measure both sides and multiply.
Circle Area
Area = pi x r squared. Where r is the radius (half the diameter). Use 3.14159 for pi or the pi button on calculators.
Triangle Area
Area = 1/2 x Base x Height. The height must be perpendicular to the base. Works for all triangle types.
Trapezoid Area
Area = 1/2 x (Base1 + Base2) x Height. Add the parallel sides, multiply by height, then divide by 2.
Parallelogram Area
Area = Base x Height. Similar to rectangle but height must be perpendicular, not the slanted side.
Regular Polygon Area
Area = 1/2 x Perimeter x Apothem. Works for any regular polygon (hexagon, octagon, etc.) with equal sides.

Practical Applications

Home & Garden

  • Calculate room floor area
  • Paint coverage estimation
  • Flooring material needs
  • Lawn and garden sizing
  • Fence planning

Construction

  • Building footprint calculation
  • Roofing material estimation
  • Concrete slab sizing
  • Wall surface area
  • Tile and brick quantities

Academic

  • Geometry homework
  • Physics calculations
  • Engineering projects
  • Architecture studies
  • Math competitions