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Board Feet Calculator

Add each board size and quantity to get the total board feet, the volume in cubic metres or yards and the running length. Enter a price per board foot for a cost estimate. Two-inch by six-inch by 12 ft is exactly 12 board feet.

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Board feet

13.2 board ft

Volume
0.04 yd³
Running length
13.2 ft
Show the working
  1. Board feet (T × W × L ÷ 12)2 × 6 × 12 ÷ 12 × 1 = 12
  2. With waste12 × (1 + 10%) = 13.2
  3. Volume0.04 yd³

Material takeoff

ItemQuantityUnit priceCost
Lumber13 board ft–
Estimated total–

Enter your local prices to estimate the cost. Prices aren't stored anywhere.

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How to use the board feet calculator

  1. Choose Imperial or Metric; board feet are always shown, along with the metric or imperial volume.
  2. Add one row per board size with its thickness, width, length and quantity.
  3. Set a waste allowance.
  4. Enter your supplier’s price per board foot in the takeoff table.

How the board feet formula works

Board feet = thickness (in) × width (in) × length (ft) ÷ 12 × quantity. Metric dimensions are converted to inches and feet first. Volume in cubic metres = board feet × 0.00236. The running length is the sum of the board lengths times their quantities, which helps when lumber is priced per linear foot or metre.

Worked examples

Construction lumber. One 2 × 6 × 12 ft = 12 board feet. With 10% waste: 13.2 board feet.

Hardwood table top. Six boards of 4/4 (1 in) × 6 in × 8 ft: 1 × 6 × 8 ÷ 12 × 6 = 24 board feet. At 20% waste, buy about 29 board feet.

Metric slab. A board 50 mm × 200 mm × 3 m is about 1.97 × 7.87 in × 9.84 ft ÷ 12 = 12.7 board feet, or 0.03 m³.

How to interpret the results

Use the board-feet total to compare prices between suppliers. For framing lumber sold per piece, the running length and piece count are more useful.

Tips and common mistakes

  • Divide by 12, not 144, when length is in feet; divide by 144 only when all three dimensions are in inches.
  • Quarter sizes: 5/4 is 1.25 in, 8/4 is 2 in.
  • Rough vs surfaced: planed stock is thinner than rough stock; ask which one the price refers to.
  • Plan cuts around defects before deciding on waste.

Board feet, linear feet and cubic metres

Lumber is priced in different ways depending on the product and the country. Hardwood dealers in North America usually quote per board foot. Softwood framing is usually sold per piece or per linear foot, and most of the world prices sawn timber per cubic metre or per linear metre for a given section. The calculator shows all three measures so you can compare offers on the same basis: board feet for hardwood, running length for priced-by-length stock and cubic metres for metric suppliers. To compare a price per cubic metre with a price per board foot, divide the cubic-metre price by about 424.

Assumptions and limitations

Boards are treated as rectangular. Live-edge and tapered pieces should be measured at their average width.

Frequently asked questions

What is a board foot?

A board foot is a volume of wood equal to 144 cubic inches: a board 1 in thick, 12 in wide and 1 ft long. It is the standard unit for hardwood lumber in North America.

How do I calculate board feet?

Multiply thickness (in) × width (in) × length (ft) and divide by 12. A 2 × 6 that is 12 ft long is 2 × 6 × 12 ÷ 12 = 12 board feet.

Should I use nominal or actual size?

Hardwood is usually sold by nominal thickness (for example 4/4 = 1 in) before surfacing. Use the convention your supplier uses for pricing, which is often the nominal size.

How many board feet are in a cubic metre?

One board foot is 144 in³, or about 0.00236 m³, so a cubic metre is about 424 board feet.

How much extra should I buy?

Woodworkers often add 15–30% for defects, grain matching and offcuts. The waste allowance starts at 10%; increase it for figured or rough-sawn stock.

Sources