Square Footage Calculator

Whether you're buying flooring, painting a room, or estimating landscaping materials, knowing the exact square footage of a space is the first step. This calculator handles any shape — rectangles, triangles, circles, and irregular rooms — in seconds.

What Does This Calculator Do?

Enter the dimensions of your space and the square footage calculator instantly returns the total area. You can add multiple rooms or sections together for whole-floor totals.

How to Use This Calculator

1. Select the shape of your area (rectangle, triangle, circle, L-shape).
2. Enter the dimensions in feet (or convert from inches).
3. Click Calculate to see the square footage.
4. Add multiple sections together for irregular floor plans.

Square Footage Formulas

• Rectangle: Length × Width
• Triangle: (Base × Height) ÷ 2
• Circle: π × Radius²
• L-Shape: Split into two rectangles, calculate each, then add.

Example Calculation

You want to tile a rectangular kitchen that is 14 ft × 11 ft plus a small pantry that is 4 ft × 3 ft.

• Kitchen: 14 × 11 = 154 sq ft
• Pantry: 4 × 3 = 12 sq ft
• Total: 166 sq ft
• Add 10% for cuts and waste: order 183 sq ft of tile.

Why Use This Calculator?

Flooring, carpet, tile, paint, and landscaping materials are all sold by the square foot or square yard. Knowing your exact area prevents buying too much (wasted money) or too little (a trip back to the store mid-project).

Common Mistakes to Avoid

• Forgetting to add a waste percentage — always add 5–15% for tile, hardwood, and laminate due to cuts and mistakes.
• Not accounting for irregular shapes — break complex rooms into simple shapes and add them together.
• Mixing inches and feet — convert all measurements to the same unit before calculating.
• Confusing sq ft and sq yd — some carpet is sold by the square yard (1 sq yd = 9 sq ft).

Frequently Asked Questions

How do I calculate square footage from inches?

Convert inches to feet first by dividing by 12. Then multiply length × width. Or enter measurements in inches and divide the result by 144.

How much paint do I need per square foot?

One gallon of paint covers roughly 350 sq ft with one coat. Divide your total wall area by 350 to find the number of gallons needed.

How do I measure a room with a closet?

Measure the main room and the closet separately, then add the square footage together for the total floor area.

What is the square footage of a standard bedroom?

A typical bedroom ranges from 100 to 200 sq ft. A master bedroom is usually 200–300 sq ft.

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

Divide the L-shape into two rectangles. Measure each rectangle, calculate each area, and add them together.

Conclusion

Square footage is one of the most fundamental measurements in home improvement, real estate, and construction. This calculator takes the guesswork out and gives you accurate numbers in seconds — no tape measure math required.

Related: Area Calculator | Tile Calculator | Concrete Calculator