Square Footage Calculator
Calculate the square footage of rooms, floors, and outdoor spaces. Supports rectangles, circles, triangles, and trapezoids.
Square Footage Calculator
Calculate area of rooms and spaces
How to Use
- 1 Select a room shape (rectangle, circle, triangle, or trapezoid)
- 2 Enter the dimensions using your preferred unit (feet, meters, etc.)
- 3 Add more rooms or areas to calculate the total square footage
- 4 Enable cost estimation to calculate material costs and waste
- 5 Copy or share the results
What You Get
A real-time square footage calculator supporting 4 shapes (rectangle, circle, triangle, trapezoid), 5 input units (ft, in, yd, m, cm), and 4 output units (sq ft, sq m, sq yd, acres). Includes multi-room support, cost estimation with adjustable waste factor, and instant results.
Input: Rectangle: 12 ft × 10 ft
Output: 120 sq ft
Input: Circle: radius 7 ft
Output: 153.94 sq ft
Input: Triangle: base 15 ft, height 8 ft
Output: 60 sq ft
Input: 3 rooms totaling 450 sq ft at $5/sq ft + 10% waste
Output: $2,475.00
How do I calculate square footage?
To calculate square footage of a rectangular room, multiply the length by the width. For example, a room that is 12 feet long and 10 feet wide is 12 × 10 = 120 square feet. For other shapes, use the appropriate formula: circles use π × r², triangles use (base × height) / 2.
How many square feet is a 12×12 room?
A 12×12 room is 144 square feet (12 × 12 = 144). This is a standard bedroom size. To convert to square meters, divide by 10.764, giving you about 13.4 square meters.
How do I calculate square footage from inches?
You can either convert inches to feet first by dividing by 12, or use our calculator and select "Inches" as your unit — it automatically converts to square feet. For example, a space that is 144 inches × 120 inches = 17,280 sq inches = 120 sq ft.
How many square feet are in an acre?
One acre is exactly 43,560 square feet. To convert square feet to acres, divide by 43,560. For example, a 10,000 sq ft lot is about 0.23 acres.
How do I calculate square footage for an irregularly shaped room?
Break the room into simple shapes — rectangles, triangles, and circles — then calculate each area separately and add them together. Our calculator lets you add multiple rooms or sections, so you can calculate each part and see the total automatically.
How much flooring do I need for my room?
Calculate the total square footage of your room, then add 10-15% for waste (cuts, mistakes, spare tiles). Our calculator includes a built-in waste factor: for a 200 sq ft room with 10% waste, you would need 220 sq ft of flooring material.
What is the difference between square feet and square meters?
1 square meter equals approximately 10.764 square feet. To convert sq ft to sq m, divide by 10.764. To convert sq m to sq ft, multiply by 10.764. Our calculator supports both units and converts automatically.
Is the square footage calculator free?
Yes, completely free with no limits. All calculations happen locally in your browser — no data is sent to any server. You can calculate as many rooms as you need.
All calculations happen locally in your browser. No data is sent to any server.