Lumber board measure / board footage
Board Foot Calculator
Ten nominal 2x6 boards 8 ft long total 80 board feet (BF). Enter the nominal thickness and width, length and number of pieces; the dressed board’s measured face is smaller.
Sources checked
Your estimate
80 board feet
2 × (6 / 12) × 8 ft × 10 boards.
- One board8 BF
- Total80 BF
- Linear feet80 ft
- Face, nominal width40 sq ft
Board measure uses nominal sizes. Actual dressed dimensions are smaller.
How to calculate board feet: the board footage formula
- The NIST PS 20 board measure formula is nominal thickness in inches × nominal width in feet × length in feet. For one 2x6 × 8 ft board: 2 × (6 / 12) × 8 = 8 BF.
- Multiply by 10 boards: 8 × 10 = 80 BF. Keep fractional BF before adding or pricing a lumber list.
- Use nominal board sizes for this tally. A dry dressed 2x6 measures 1.5 × 5.5 in under the standard, but substituting those dimensions would calculate physical volume, not this board measure; the real sizes are on 2x6 actual size and the nominal vs actual lumber sizes table.
The board measure definition and its limits come from the U.S. softwood lumber standard. NIST PS 20-25, American Softwood Lumber Standard (Jan 2025)
- Dry dressed 2 in nominal thickness
- 1.5 in actualNIST PS 20-25, American Softwood Lumber Standard (Jan 2025)
- Dry dressed 6 in nominal width
- 5.5 in actualNIST PS 20-25, American Softwood Lumber Standard (Jan 2025)
- Common stock length increment
- 2 ftNIST PS 20-25, American Softwood Lumber Standard (Jan 2025)
Board feet per common board
| Nominal size | Actual dry face | Per linear foot | 8 ft | 10 ft | 12 ft |
|---|---|---|---|---|---|
| 2x4 | 1.5 × 3.5 in | 0.67 BF | 5.33 BF | 6.67 BF | 8 BF |
| 2x6 | 1.5 × 5.5 in | 1 BF | 8 BF | 10 BF | 12 BF |
| 2x8 | 1.5 × 7.25 in | 1.33 BF | 10.67 BF | 13.33 BF | 16 BF |
| 2x10 | 1.5 × 9.25 in | 1.67 BF | 13.33 BF | 16.67 BF | 20 BF |
| 2x12 | 1.5 × 11.25 in | 2 BF | 16 BF | 20 BF | 24 BF |
Board feet to square feet
| Nominal thickness | 1 BF covers | 100 BF cover |
|---|---|---|
| 1 in | 1 sq ft | 100 sq ft |
| 2 in | 0.5 sq ft | 50 sq ft |
| 3 in | 0.33 sq ft | 33.33 sq ft |
| 4 in | 0.25 sq ft | 25 sq ft |
The dressed faces of the boards in the table above are on 2x4 actual size, 2x6 actual size, 2x8 actual size and 2x10 actual size.
How other calculators count
Ten nominal 2x6 boards, 8 ft long
- 80 BFDIYCalcs Board Foot Calculator (run 13 Oct 2026)
- 80 BFJobsite Calcs Board Foot Calculator (run 13 Oct 2026)
- 80 BFCalcShed Lumber Calculator (run 13 Oct 2026)
All three match the 80 BF nominal-size tally. NIST PS 20 warns that “board foot” is not a well-defined physical volume unit, so this is a lumber trade measure rather than a cubic-foot conversion.
Board foot questions
How do you calculate board feet?
Board footage is nominal thickness in inches times nominal width in inches, divided by 12, times length in feet. One 2x6 8 ft long is 2 × 6 ÷ 12 × 8 = 8 BF, and 10 of them are 80 BF.
How many board feet in a 2x6x8 or a 2x4x8?
8 BF for the 2x6x8 and 5.33 BF for the 2x4x8, both from nominal dimensions. The dry dressed 2x4 is 1.5 × 3.5 in, which is not substituted into the board measure; see 2x4 actual size for the real face.
How do I convert board feet to square feet?
Divide the board feet by the nominal thickness in inches. One board foot covers 1 sq ft of 1 in stock and 0.5 sq ft of 2 in stock, so the 80 BF in the example are 40 sq ft of nominal face.
How do I convert linear feet to board feet?
Multiply the linear feet by the board feet in one foot of that size. A 2x6 holds 1 BF in each foot of length, so 8 linear feet are 8 BF. Going back, divide the board feet by that figure.
How do I work out the price per board foot?
Divide the price by the board feet. A 2x6x8 holds 8 BF, so its price divided by 8 is its price per board foot. A price per thousand board feet (MBF) is a thousand times the price per BF; 80 BF is 0.08 MBF.
Should I use actual or nominal lumber size?
Use nominal thickness and width for the NIST PS 20 board measure tally. For fit and cut lists, use the measured actual size instead.
Is a board foot one twelfth of a cubic foot?
Nominal arithmetic resembles that conversion, but NIST PS 20 explicitly gives no physical-volume conversion for board foot because it is not a well-defined unit of volume. Do not use this tally as concrete or storage volume.
Does this calculator work for logs?
No. It counts sawn lumber from its nominal size. Log scales such as Doyle estimate the lumber a log will saw into, which is a different calculation.
A planning aid, not an engineering calculation: your local code and building inspector have the final word. Terms