Board Feet Calculator

Calculate board feet of lumber from thickness, width, and length. Estimate total board footage for multiple pieces and plan your lumber purchases.

Board Feet per Piece
10.00
2" x 6" x 120" / 144
Total Board Feet
80.00
10.00 BF x 8 boards
Waste-Adjusted BF (10%)
88.00
Order this amount to account for waste and defects
Total Cost
$308.00
At $3.50/BF including 10% waste
Cost per Board
$35.00
Single board cost before waste adjustment
Cost per Linear Foot
$3.50
Total linear feet: 80.0
Total Weight
200 lbs
25.0 lbs per board
SizeActual TActual WBF/8ftBF/10ftBF/12ft
1x40.75"3.5"1.752.192.63
1x60.75"5.5"2.753.444.13
1x80.75"7.25"3.634.535.44
1x120.75"11.25"5.637.038.44
2x41.5"3.5"3.504.385.25
2x61.5"5.5"5.506.888.25
2x81.5"7.25"7.259.0610.88
2x101.5"9.25"9.2511.5613.88
2x121.5"11.25"11.2514.0616.88
4x43.5"3.5"8.1710.2112.25
6x65.5"5.5"20.1725.2130.25
Planning notes, formulas, and examples

About the Board Feet Calculator

Board feet (BF) is the standard unit of measure for hardwood lumber in North America. One board foot equals a piece of wood 1 inch thick, 12 inches wide, and 12 inches long—or 144 cubic inches of wood. Whether you're buying rough-sawn hardwood from a sawmill, pricing exotic species at a specialty dealer, or estimating material for a woodworking project, knowing how to calculate board feet is essential.

This board feet calculator lets you enter the thickness in inches, width in inches, and length in feet for each piece of lumber, then computes the board footage quickly. You can add multiple pieces with different dimensions and quantities to build a running total, making it easy to create a complete lumber order.

Understanding board feet helps you compare prices across suppliers, convert between different lumber dimensions, and estimate project costs accurately. Sawmills and hardwood dealers price lumber per board foot, so a quick calculation before you buy ensures you know exactly what you're paying for.

When This Page Helps

Every woodworker, cabinet maker, and framing contractor needs to estimate lumber quantities in board feet. This calculator eliminates mental math errors, handles multiple piece sizes at once, and gives you a running total you can take to the lumber yard. It's especially useful when working with rough-sawn hardwoods priced by the board foot rather than by the linear foot.

How to Use the Inputs

  1. Enter the thickness of the lumber in inches (e.g., 1 for 4/4 stock, 2 for 8/4).
  2. Enter the width of the board in inches.
  3. Enter the length of the board in feet.
  4. Enter the number of identical pieces you need.
  5. Read the board feet per piece and total board feet for all pieces.
  6. Adjust dimensions or quantities as needed to finalize your order.
Formula used
Board Feet (BF) = (Thickness″ × Width″ × Length') / 12 Total BF = BF per piece × Quantity Where thickness and width are in inches and length is in feet.

Example Calculation

Result: 80 board feet

Each 2″ × 6″ × 10' board contains (2 × 6 × 10) / 12 = 10 board feet. With 8 pieces the total is 10 × 8 = 80 board feet. At $5 per board foot, this order would cost $400.

Tips & Best Practices

  • Use nominal dimensions for softwood (e.g., a 2×4 is actually 1.5″×3.5″) but actual dimensions for rough-sawn hardwood.
  • Round up partial board feet when ordering—suppliers won't sell fractions of a board.
  • Add 10–15% extra for waste due to defects, miscuts, and end-checking.
  • Convert quarter designations: 4/4 = 1″, 5/4 = 1.25″, 6/4 = 1.5″, 8/4 = 2″.
  • Check whether your supplier measures width at the widest point, narrowest point, or average for irregular boards.
  • Kiln-dried lumber may be slightly thinner than the nominal thickness after surfacing.

How Board Feet Are Used in the Lumber Industry

Board feet remain the universal measurement for trading hardwood lumber. Sawmills, wholesalers, and retail hardwood dealers all price their inventory per board foot, making it essential for anyone purchasing wood in bulk. Softwoods for framing are more commonly sold by the linear foot or per piece, but converting to board feet allows apples-to-apples cost comparisons across species and suppliers.

Common Hardwood Prices per Board Foot

Prices vary by species, grade, and region. As of 2025, poplar runs $3–4/BF, red oak $5–7/BF, white oak $6–9/BF, hard maple $6–8/BF, cherry $7–10/BF, and walnut $8–15/BF. Exotic species like purpleheart or zebrawood can exceed $20/BF. FAS (First and Seconds) grade commands a premium over #1 Common.

Board Foot vs. Linear Foot

A linear foot measures only length, ignoring thickness and width. A board foot accounts for all three dimensions. A 10-foot board that is 1″ × 6″ contains 5 board feet, while a 10-foot board that is 2″ × 12″ contains 20 board feet—even though both are 10 linear feet long. Always confirm which unit your supplier uses before placing an order.

Sources & Methodology

Last updated:

Frequently Asked Questions

  • A board foot is a unit of volume equal to 144 cubic inches of wood. It corresponds to a piece 1 inch thick, 12 inches wide, and 1 foot long. It is the standard pricing unit for hardwood lumber in the United States and Canada.