Square feet tells you surface coverage. Board feet tells you lumber volume. To move from one to the other, you need to know the board thickness.
Rule
Once thickness is known, the conversion is straightforward:
Board Feet = Square Feet x Thickness in inches
If you have 100 square feet of boards that are 1 inch thick, you have 100 board feet. If those boards are 2 inches thick, you have 200 board feet.
Mini Converter
Enter coverage area and thickness. The converter multiplies them using the standard thickness rule.
Quick Factors
| Thickness | Multiplier | 100 sq ft equals |
|---|---|---|
| 1/2 inch | 0.50 | 50 board feet |
| 3/4 inch | 0.75 | 75 board feet |
| 1 inch | 1.00 | 100 board feet |
| 5/4 inch | 1.25 | 125 board feet |
| 2 inches | 2.00 | 200 board feet |
When this helps
If thickness changes across items, switch back to the main board foot calculator and price each line separately.