What is square foot?

A square foot is a unit of area in imperial and US customary systems equal to 144 square inches. It is commonly used in the United States for real estate listings, floor plans, and building layouts.

What is square inch?

A square inch is a unit of area in imperial and US customary systems equal to 1/144 of a square foot. It is used for measuring small surfaces, printed circuit boards, and product specifications in imperial-based industries.

Worked examples

1 square foot = 144 square inch

1 square inch = 0.00064516 square metre