What is a board foot?

A board foot (BF) is a unit of lumber volume equal to a piece of wood 1 inch thick, 12 inches wide, and 12 inches long. 1 BF = 1" × 12" × 12" = 144 cubic inches Formula: BF = (Thickness_in × Width_in × Length_ft) / 12 Or equivalently: BF = (Thickness_in × Width_in × Length_in) / 144 Examples: • 1×6, 8 ft: (1 × 6 × 8) / 12 = 4.0 BF • 2×4, 8 ft: (2 × 4 × 8) / 12 = 5.33 BF • 2×6, 10 ft: (2 × 6 × 10) / 12 = 10.0 BF • 4×4, 12 ft: (4 × 4 × 12) / 12 = 16.0 BF Board feet measure volume. Linear feet measure only length.

Do I use nominal or actual dimensions for board feet?

Use NOMINAL dimensions — the labeled size, not the actual milled dimensions. Nominal vs actual: • 1×4 nominal → 0.75" × 3.5" actual • 1×6 nominal → 0.75" × 5.5" actual • 2×4 nominal → 1.5" × 3.5" actual • 2×6 nominal → 1.5" × 5.5" actual • 4×4 nominal → 3.5" × 3.5" actual • 6×6 nominal → 5.5" × 5.5" actual Always use the nominal (labeled) size for the board feet formula, because lumber is bought, sold, and priced using nominal dimensions. If you used actual dimensions, your quantity calculation would not match the supplier's pricing.

MBF stands for 'thousand board feet' (M is the Roman numeral for 1,000). It is used for large wholesale lumber orders. 1 MBF = 1,000 board feet Example: A framing package for a house might be quoted as '$2,800 per MBF' — meaning $2.80 per board foot. Conversion: • Price per BF = Price per MBF / 1,000 • Total cost = BF × (MBF price / 1,000) Retail lumber yards typically price per linear foot or per board foot. Wholesale suppliers and sawmills typically use MBF pricing.

How do I convert linear feet to board feet?

Linear feet (LF) only measures length — it ignores thickness and width. To convert to board feet: BF = Linear feet × (Thickness_in × Width_in) / 12 Examples: • 100 LF of 2×6: 100 × (2 × 6) / 12 = 100 BF • 100 LF of 2×4: 100 × (2 × 4) / 12 = 66.67 BF • 100 LF of 1×6: 100 × (1 × 6) / 12 = 50 BF Note: 2×6 happens to equal its linear footage in board feet (any lumber where T × W = 12 has this property). This is why 2×6 decking is sometimes priced the same per LF as per BF.

How many board feet are in a 2×4×8?

A standard 2×4 stud at 8 feet = 5.33 board feet. Calculation: (2 × 4 × 8) / 12 = 64/12 = 5.333 BF Other common stud lengths: • 2×4 × 7 ft (precut stud): 4.67 BF • 2×4 × 8 ft: 5.33 BF • 2×4 × 10 ft: 6.67 BF • 2×4 × 12 ft: 8.00 BF • 2×4 × 16 ft: 10.67 BF For a wall with 16" stud spacing, you need approximately 1 stud per linear foot of wall plus extras for corners, headers, and blocking. A typical 8-ft wall with 10 studs uses 10 × 5.33 = 53.3 BF of 2×4.

What is the difference between softwood and hardwood pricing?

Softwood lumber (pine, fir, spruce — used for framing): • Typically priced per linear foot at retail or per MBF wholesale • 2×4 stud: $3–$6 per 8-ft board (retail, varies widely by region) • Framing lumber wholesale: $500–$800/MBF (fluctuates with market) Hardwood lumber (oak, maple, walnut, cherry — used for furniture/woodworking): • Almost always priced per board foot • Common species: $4–$8/BF (poplar, ash, red oak) • Premium species: $8–$15/BF (hard maple, cherry) • Exotic/figured: $15–$50+/BF (walnut, figured maple, exotic species) Hardwoods are sold in random widths and lengths (RWL) — you buy what the log yields. Softwoods are sold in standard dimensioned sizes (2×4, 2×6, etc.).

Board Feet Calculator — Lumber Volume & Cost

The Board Feet Calculator converts lumber dimensions into board feet — the standard unit for buying and pricing lumber in the US. Select your nominal lumber size from 16 common presets (1×2 through 6×6), enter the board length and quantity, and the calculator instantly outputs board feet per board and total board feet ..

LUMBER LIST

BOARD 1

5.333 BF

NOMINAL SIZE

THICK (in)

WIDTH (in)

LENGTH (ft)

QTY

Per board: 5.333 BF · 1 board5.333 BF total

PRICE (optional)

Common lumber pricing: framing 2×4 ~$0.70–$1.20/LF · hardwoods $3–$15/BF · MBF = price per 1,000 board feet

TOTAL RESULTS

TOTAL BOARD FEET

5.33 BF

= 0.0053 MBF

BOARD VISUALISER (not to scale)

PROJECT SUMMARY

Total board feet5.333 BF

Total MBF0.0053 MBF

Total board count1 boards

BF PER 8 FT BOARD — REFERENCE

1×21.333

1×32.000

1×42.667

1×64.000

1×85.333

1×106.667

1×128.000

2×22.667

2×45.333

2×68.000

2×810.667

2×1013.333

2×1216.000

4×410.667

4×616.000

6×624.000

KEY FACTS

1 BF = 1" × 12" × 12" = 144 cubic inches

Formula: (T_in × W_in × L_ft) / 12

Uses NOMINAL dimensions (as labeled)

2×4 nominal = 1.5"×3.5" actual (but calc as 2×4)

1 MBF = 1,000 board feet

1 BF ≈ 0.00236 cubic metres

Created with❤️byeaglecalculator.com

HOW TO USE

1
Select your nominal lumber size using the preset buttons (1×2 through 6×6) or type custom thickness and width values in inches. Use nominal dimensions — the labeled size, not the actual milled size. A 2×4 is labeled as 2×4 even though its actual dimensions are 1.5"×3.5". The board feet formula uses the nominal figure.
2
Enter the board length in feet using the quick preset buttons (6, 8, 10, 12, 14, 16 ft are the most common stock lengths) or type a custom length. Then enter your quantity — how many boards of that size and length you need.
3
Click '+ Add another lumber size' to add a second, third, or more rows for mixed lumber orders. Each row calculates independently and the grand total accumulates at the bottom. The 3D board visualiser on the right updates to show the first board's proportions.
4
Optionally enter a price — either per board foot (common for hardwoods) or per MBF (1,000 board feet, common for wholesale framing lumber). The calculator converts between the two and applies it to your total board feet.
5
Read your results: board feet per row, grand total BF, total in MBF, and material cost. The reference table on the right shows board feet per 8-ft board for all common sizes, with your current selection highlighted.

WORKED EXAMPLE

Board feet for a deck framing project: Materials needed: • 12 pcs of 2×8 × 12 ft (joists) • 3 pcs of 2×10 × 16 ft (beams) • 20 pcs of 2×6 × 10 ft (decking) Step 1: Calculate each size 2×8 × 12 ft: (2 × 8 × 12) / 12 = 16.0 BF per board × 12 = 192.0 BF 2×10 × 16 ft: (2 × 10 × 16) / 12 = 26.67 BF per board × 3 = 80.0 BF 2×6 × 10 ft: (2 × 6 × 10) / 12 = 10.0 BF per board × 20 = 200.0 BF Step 2: Grand total 192.0 + 80.0 + 200.0 = 472.0 BF total = 0.472 MBF Step 3: Cost at $3.50/BF 472.0 × $3.50 = $1,652.00 Step 4: Cost at $3,500/MBF (wholesale check) 0.472 × $3,500 = $1,652.00 (same result — consistent)

FREQUENTLY ASKED QUESTIONS

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Last updated: April 29, 2026 · Formula verified by EagleCalculator team · Eagle-eyed accuracy for every calculation.