📐 Square Footage Calculator

Calculate area for any shape. Convert between square feet, meters, yards, and acres. Estimate cost per square foot.

Area (per shape) 300 sq ft
Total Area 300 sq ft
Square Meters 27.87 m²
Square Yards 33.33 yd²
Square Inches 43,200 in²
Acres 0.0069 acres

How to Calculate Square Footage

Square footage is the area measured in square feet. For rectangles, multiply length by width. For other shapes, use the formula specific to that shape.

Area Formulas by Shape

Rectangle/Square: Length × Width
Circle: π × radius²
Triangle: ½ × base × height
Trapezoid: ½ × (base₁ + base₂) × height

Area Conversion Reference

Quickly convert between common area units:

From To Multiply By Example
sq ft sq m 0.0929 500 sq ft = 46.45 m²
sq m sq ft 10.764 50 m² = 538.2 sq ft
sq ft sq yd 0.1111 900 sq ft = 100 sq yd
sq ft acres 0.0000230 43,560 sq ft = 1 acre
acres sq ft 43,560 0.5 acre = 21,780 sq ft
sq ft sq in 144 1 sq ft = 144 sq in

Common Room Sizes

Room Typical Size Square Feet
Small Bedroom 10×10 ft 100 sq ft
Standard Bedroom 12×12 ft 144 sq ft
Master Bedroom 14×16 ft 224 sq ft
Bathroom 5×8 ft 40 sq ft
Kitchen 12×12 ft 144 sq ft
Living Room 16×20 ft 320 sq ft
One-Car Garage 12×20 ft 240 sq ft
Two-Car Garage 24×24 ft 576 sq ft

Frequently Asked Questions

How do I calculate square footage?

For rectangles, multiply Length × Width. A 20ft × 15ft room = 300 square feet. For circles, use π × radius². For triangles, use ½ × base × height. Our calculator supports 6 different shapes.

How many square feet in an acre?

One acre equals 43,560 square feet. That's roughly the size of a football field (without end zones). A half acre is 21,780 sq ft, and a quarter acre is 10,890 sq ft.

How to convert square feet to square meters?

Multiply square feet by 0.0929 to get square meters. For example, 500 sq ft = 46.45 m². To convert m² back to sq ft, multiply by 10.764.

What is the square footage of a 12×12 room?

A 12×12 room is 144 square feet. This is a standard bedroom size. You'd need about 144 sq ft of flooring material plus 10% wastage (about 159 sq ft total).

How do I calculate square footage of an L-shaped room?

Divide the L-shape into two rectangles, calculate each area separately (length × width), then add them together. For example, if one section is 10×12 ft and the other is 8×6 ft, total = 120 + 48 = 168 sq ft.

How many square feet is a 10×10 room?

A 10×10 room is 100 square feet. This is a common small bedroom or home office size. For reference, 100 sq ft ≈ 9.29 square meters.

How do I measure square footage for flooring?

Measure each room's length and width in feet, then multiply to get square footage. For irregular rooms, break them into rectangles and add areas together. Always add 10% for cuts and waste when ordering flooring materials.

What is the formula for area of a circle?

Area = π × r² (pi times radius squared). For a circle with a 10ft diameter: radius = 5ft, area = 3.14159 × 25 = 78.5 square feet. This is useful for round patios, pools, and garden beds.