How do I calculate square footage for an irregular room?

Divide the room into rectangles, calculate each separately, then add the results. The multi-room feature lets you add each section as its own entry.

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

A 12 ft × 12 ft room is 144 square feet.

Square Footage Calculator

Shape

Length (ft)

Width (ft)

Enter dimensions above

Multi-room total

Total 0 sq ft

How to Calculate Square Footage

Rectangle / Room Length x Width

A 12 ft x 10 ft room = 120 sq ft

Circle pi x radius²

A circular patio with 8 ft radius = 201 sq ft

Triangle 0.5 x Base x Height

A triangular garden 20 ft base, 12 ft high = 120 sq ft

L-Shape Rectangle A + Rectangle B

Split the L into two rectangles and add areas together

Common Square Footage Reference

US median home (2023) 2,014 sq ft

1-car garage 200-250 sq ft

Master bedroom 200-300 sq ft

Standard bedroom 120-150 sq ft

Basketball court 4,700 sq ft

Tennis court 2,808 sq ft

1 acre 43,560 sq ft

Frequently Asked Questions

How do I measure an irregular room?

Break the room into simple shapes (rectangles, triangles) and calculate each section separately. Use the multi-room tool to add all sections together. For L-shaped rooms, use the L-Shape mode which handles this automatically with two rectangular sections.

How many square feet is a 12x12 room?

A 12 x 12 foot room is 144 square feet (12 x 12 = 144). This is about the size of a standard bedroom. Add 10-15% for waste when calculating flooring or painting materials.

How do I convert square feet to square meters?

Multiply square feet by 0.0929 to get square meters. The calculator does this conversion automatically. For rough estimates: 100 sq ft is about 9.3 sq m; 500 sq ft is about 46.5 sq m.