BuildRight
Lumber Board Foot Calculator
The volume-based unit hardwood and specialty lumber is priced by, not the same as a linear foot.
Board feet for common lumber dimensions
A board foot is 144 cubic inches: thickness in inches times width in inches times length in feet, divided by 12. Hardwood is priced this way rather than by the piece.
| Nominal size | Length | Board feet |
|---|---|---|
| 1 x 4 | 10 ft | 3.333 |
| 1 x 6 | 8 ft | 4.000 |
| 1 x 8 | 8 ft | 5.333 |
| 1 x 12 | 8 ft | 8.000 |
| 2 x 6 | 8 ft | 8.000 |
| 2 x 10 | 12 ft | 20.000 |
| 1.5 x 12 | 16 ft | 24.000 |
Use nominal thickness for pricing but remember that surfaced lumber is thinner than nominal: a 1-inch board finishes at 3/4 inch and a 2 by 4 is actually 1.5 by 3.5. Hardwood is often sold in quarters, where 4/4 means one nominal inch.
Board foot vs. linear foot
A linear foot just measures length regardless of thickness or width; a board foot measures actual volume (1" × 12" × 12" = 1 board foot) — hardwood lumber is typically priced per board foot, while dimensional softwood lumber (2x4s, etc.) is usually priced per linear foot.
Nominal vs. actual dimensions
A '2×4' isn't actually 2 inches by 4 inches — it's closer to 1.5" × 3.5" after milling and drying. Use actual (not nominal) dimensions in this calculator for an accurate board foot count.
Frequently asked questions
I need a 2-inch thick, 8-inch wide, 10-foot long board — how many board feet is that?
About 13.3 board feet (2 x 8 x 120 inches / 144 = 13.33 BF). At $8/board foot for walnut, that single board would cost about $107.
What's the difference between a board foot and a linear foot?
A linear foot measures only length. A board foot measures volume (1" x 12" x 12"). Hardwood lumber is priced per board foot because thickness and width vary. Dimensional softwood (2x4s) is priced per linear foot because the cross-section is standard.
Should I use nominal or actual dimensions?
Use actual dimensions for an accurate board foot calculation. A nominal '2x4' is actually 1.5" x 3.5" after milling. When buying rough-sawn hardwood, the nominal size is closer to actual since it hasn't been planed yet.
How does this relate to the stud framing calculator?
The stud framing calculator tells you how many studs you need for a wall. This board foot calculator helps price specialty or hardwood lumber. Standard framing lumber (2x4s, 2x6s) is typically priced per linear foot, not per board foot.
Related Home & DIY calculators
Last updated: September 7, 2026