Square Footage Calculator

Calculate room area in sq ft, sq meters, and sq yards

Shape
ft
ft
Total Area
300.00 ft²
20 × 15 ft rectangle
Sq Feet300.00 ft²
Sq Meters27.87 m²
Sq Yards33.33 yd²
Sq Inches43,200 in²

How to Measure Square Footage

Use a tape measure to find the length and width of the room in feet. Measure from wall to wall at the widest points. Multiply length × width for the area in square feet.

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Flooring tip: Always add 10% extra to your square footage for cuts, waste, and pattern matching. For a 300 sq ft room, order 330 sq ft of flooring.

For irregular rooms, break the space into rectangles and add the areas together — use L-Shape mode above for rooms with one corner cutout.

Formulas by Shape

Rectangle: Area = Length × Width
Triangle: Area = ½ × Base × Height
Circle: Area = π × Radius² (π ≈ 3.14159)
L-Shape: Area = Rectangle A + Rectangle B

Common Room Sizes

Room TypeTypical SizeSquare Footage
Small Bedroom10×10 ft100 ft²
Standard Bedroom12×12 ft144 ft²
Master Bedroom14×16 ft224 ft²
Living Room15×18 ft270 ft²
Large Living Room20×20 ft400 ft²
Kitchen10×12 ft120 ft²
Bathroom5×8 ft40 ft²
Garage (1-car)12×20 ft240 ft²
Garage (2-car)20×22 ft440 ft²

Unit Conversions

FromToMultiply By
Square feet (ft²)Square meters (m²)× 0.0929
Square feet (ft²)Square yards (yd²)÷ 9
Square feet (ft²)Square inches (in²)× 144
Square feet (ft²)Acres÷ 43,560
Square meters (m²)Square feet (ft²)× 10.764

What Can You Calculate?

🪵FlooringHardwood, tile, or carpet
🎨Painting1 gallon ≈ 350 sq ft wall
🏡Real EstateCompare home sizes
☀️Solar PanelsRoof coverage planning
🌱Garden / LawnFertilizer & grass seed
📦StorageFurniture layout planning

Common Square Footage Mistakes to Avoid

  • Not adding 10% waste factor — always order 10–15% extra flooring for cuts, mistakes, and future repairs.
  • Mixing inches and feet — a room that is 12 feet 6 inches wide is 12.5 feet, NOT 12.6. Convert: inches ÷ 12.
  • Measuring to the wrong point — for flooring, measure wall to wall at the widest point.
  • Forgetting odd-shaped rooms — break L-shaped or irregular rooms into rectangles, calculate each separately, then add.

Frequently Asked Questions

How many square feet is a 12×12 room?

A 12×12 room is 144 square feet. Calculation: 12 ft × 12 ft = 144 ft².

How much flooring do I need for a 300 sq ft room?

Buy approximately 330 sq ft of flooring (300 × 1.10). Always add 10% for waste, cuts, and future repairs.

How do I convert square feet to square meters?

Multiply by 0.0929. Example: 300 ft² × 0.0929 = 27.87 m². The calculator shows this automatically.

How many square feet are in an acre?

There are 43,560 square feet in 1 acre. An acre is roughly the size of a football field without the end zones.

How many square feet is a 10×10 room?

A 10×10 room is 100 square feet. Typical small bedroom or large bathroom size.

How do I calculate square footage from inches?

Multiply length × width in inches to get square inches, then divide by 144. Formula: sq ft = (in × in) ÷ 144. Or enter measurements in decimal feet (6 inches = 0.5 ft).

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