How to use this calculator
- Enter linear feet. The total length of material you have or need.
- Enter the width. Width in feet. Use the presets (6", 8", 12", 4 ft sheet) or type a custom width.
- Read the square footage. The primary result is ft². The stats include yd² and m² for cross-quoting.
Formula
Square Feet = Linear Feet × Width (ft)
Worked example
120 linear feet of 6-inch (0.5 ft) hardwood plank covers 120 × 0.5 = 60 square feet. A 12 × 5 ft hallway needs 60 ft², so this is exactly right (no waste built in — add 10%).
Tips for accurate results
- Plank widths are the actual face width, not the nominal size. A "6 inch" plank may measure 5.5" — convert to feet (0.458) for the math.
- Always add 10% waste on flooring jobs and 15% if running diagonal — cuts and end-pieces vanish into the trash bin.
- For sheet goods (4×8 plywood), each linear foot of an 8-ft sheet covers 4 ft².
- Crown molding, chair rail, and baseboard are sold by the linear foot — width does not factor in for those, just length.