Measure the room’s length in feet
Measure the room’s width in feet
Multiply length by width
Use the formula: square feet = length × width
For irregular rooms, divide the room into smaller rectangles
Measure each section separately
Calculate the square feet of each section
Add all section totals together
Subtract any areas not included, such as closets or cutouts, if needed
Round measurements to the nearest inch or fraction of a foot if necessary