Profession Calculators
Construction & Engineering

Lumber Board Foot Calculator

Calculate total board feet for lumber orders from thickness, width, length, and quantity with cost estimation.

Lumber Pieces

Board Foot = (Thickness x Width x Length in ft) / 12. Uses nominal dimensions.

What This Calculator Does

This calculator computes the total board footage for lumber orders based on the thickness, width, length, and quantity of each piece. Board feet are the standard unit of measurement for hardwood lumber purchasing and pricing. It also estimates total cost based on price per board foot.

The Formula

Board Feet = (Thickness in inches x Width in inches x Length in feet) / 12

One board foot equals a piece of lumber 1 inch thick, 12 inches wide, and 1 foot long (144 cubic inches). The formula multiplies nominal thickness by nominal width (both in inches) by length (in feet), then divides by 12. A 2x6x8 piece contains (2 x 6 x 8) / 12 = 8 board feet.

Step-by-Step Example

1

Enter piece dimensions

Use nominal dimensions (as lumber is sold, not actual). A "2x6" is entered as 2" thick and 6" wide. Enter length in feet.

2

Set quantity

How many pieces of each size you need. Example: 10 pieces of 2x6x8.

3

Add additional pieces

Click "Add Piece" for each different lumber size in your order. Common projects mix multiple dimensions.

4

Enter price per board foot

Hardwood prices range from $3-$15+ per board foot depending on species and grade. Example: Red Oak at $5.50/BF.

Real-World Use Cases

Hardwood Lumber Purchasing

Calculate the board footage for furniture projects, cabinetry, or millwork to get accurate quotes from lumber yards.

Project Cost Estimation

Estimate material costs for woodworking projects before committing to a design.

Sawmill Orders

Specify exact board footage when ordering custom-sawn lumber from a sawmill or specialty dealer.

Common Mistakes to Avoid

  • Using actual dimensions instead of nominal. Lumber is sold by nominal size (2x4, 2x6) but the actual dimensions are smaller (1.5x3.5, 1.5x5.5). Board foot calculations use nominal dimensions.

  • Confusing board feet with linear feet. A 2x6x8 is 8 linear feet but 8 board feet. A 1x6x8 is 8 linear feet but only 4 board feet.

  • Not accounting for waste and defects when ordering rough-sawn hardwood. Add 20-25% for planing, jointing, and cutting around defects.

Frequently Asked Questions

Accuracy and Disclaimer

Board foot calculations use nominal dimensions as is standard in the lumber industry. Actual lumber dimensions are smaller than nominal. Prices vary significantly by species, grade, region, and market conditions. Verify pricing with your lumber supplier.