Square Inches Calculator
Find an area in square inches from length and width in any unit.
Change the values and press Calculate to work out your own figures.
Enter the rectangle's sizes.
Show the working
- area = length × width
How to use it
Enter the rectangle's sizes.
Lengths can be decimals, fractions or tape entries such as 12' 6 1/2" (in feet or inches). Prices are optional.
Key facts
rectangle = length × width; circle = π r²; triangle (Heron) = √(s(s − a)(s − b)(s − c))
Units
A square yard is 9 square feet, a square foot 144 square inches, and a square meter about 10.764 square feet.
Questions
How many square inches in a square foot?
144.
Formulas
rectangle = length × width; circle = π r²; triangle (Heron) = √(s(s − a)(s − b)(s − c))
Sources
Limitations
- Material densities are typical values (the midpoint of the commonly published range); real loads vary with moisture, grading and compaction, so check with your supplier or type in their density.
- Tank results are the geometric volume; real tanks have wall thickness and fittings.