Board Feet Calculator

Professional Lumber Volume Calculator & Measurement Tool

Calculate Board Feet

Total Board Feet

4

BF

Formula Used

(L × W × T) ÷ 144 × Qty

Length, width, and thickness in inches

Quick Presets

Accurate Measurements

Calculate precise board feet for hardwood, softwood, and dimensional lumber using standard industry formulas.

Educational Resources

Learn lumber grading, wood species characteristics, and timber measurement standards from forestry experts.

Cost Estimation

Estimate lumber costs for woodworking projects, construction, and furniture making with accurate volume calculations.

What is a Board Foot?

A board foot is a standard unit of measurement for lumber volume in the United States and Canada. One board foot represents the volume of a board that is 12 inches long, 12 inches wide, and 1 inch thick (144 cubic inches). Understanding board feet is essential for purchasing lumber, estimating material costs, and planning woodworking or construction projects.

The board foot measurement system is used extensively in the timber industry, sawmills, lumber yards, and by professional woodworkers. Unlike linear feet, which only measure length, board feet account for the three-dimensional volume of wood, making it ideal for pricing and inventory management of dimensional lumber, hardwood boards, and rough-sawn timber.

Board Feet Formula

Board Feet = (Length in inches × Width in inches × Thickness in inches) ÷ 144

For length measured in feet, multiply by 12 before calculating. This formula is standardized by the National Institute of Standards and Technology (NIST) and used throughout the North American lumber industry.

How to Calculate Board Feet

  1. Measure the lumber dimensions: Use a tape measure to determine the length, width, and thickness of your board. Measure thickness and width at the narrowest points for accuracy.
  2. Convert to inches: Ensure all measurements are in inches. If length is in feet, multiply by 12.
  3. Apply the formula: Multiply length × width × thickness, then divide by 144.
  4. Multiply by quantity: If calculating multiple pieces, multiply the result by the number of boards.

Common Lumber Dimensions

Dimensional lumber is sold in nominal sizes that differ from actual dimensions. For example, a "2×4" actually measures 1.5 × 3.5 inches after planing and drying. Always use actual dimensions when calculating board feet for precision.

Board Feet Conversion Charts

Common Dimensional Lumber (8-foot boards)

Nominal SizeActual SizeBoard Feet (8 ft)Board Feet (10 ft)Board Feet (12 ft)
1×40.75" × 3.5"2.33 BF2.92 BF3.50 BF
1×60.75" × 5.5"3.67 BF4.58 BF5.50 BF
2×41.5" × 3.5"4.67 BF5.83 BF7.00 BF
2×61.5" × 5.5"7.33 BF9.17 BF11.00 BF
2×81.5" × 7.25"9.67 BF12.08 BF14.50 BF
2×101.5" × 9.25"12.33 BF15.42 BF18.50 BF
2×121.5" × 11.25"15.00 BF18.75 BF22.50 BF
4×43.5" × 3.5"8.17 BF10.21 BF12.25 BF

Hardwood Thickness Comparison

Rough ThicknessSurfaced Thickness (S2S)Quarter SystemCommon Uses
1"13/16" (0.8125")4/4Furniture, cabinets, paneling
1.25"1.0625"5/4Table tops, benches
1.5"1.3125"6/4Counter tops, stair treads
2"1.75"8/4Structural beams, thick furniture
3"2.75"12/4Heavy beams, wood turning

Lumber Types and Applications

Dimensional Lumber (Softwood)

Primarily from coniferous trees like pine, fir, and spruce. Used extensively in construction framing, decking, and general building projects. Sold in standardized nominal sizes.

  • Cost-effective for framing and structural applications
  • Readily available at lumber yards and home centers
  • Pressure-treated options for outdoor use

Hardwood Lumber

From deciduous trees including oak, maple, cherry, and walnut. Priced by board foot and graded by quality. Ideal for fine woodworking, furniture, and cabinetry.

  • Superior durability and aesthetic appeal
  • Measured using board feet calculation
  • Graded by NHLA standards (FAS, Select, Common)

Popular Wood Species

Pine

Density: 25-30 lb/ft³

Use: Construction, furniture

Oak

Density: 37-56 lb/ft³

Use: Flooring, cabinetry

Maple

Density: 39-47 lb/ft³

Use: Furniture, cutting boards

Cherry

Density: 35-38 lb/ft³

Use: Fine furniture, cabinets

Walnut

Density: 38-43 lb/ft³

Use: Premium furniture

Cedar

Density: 22-31 lb/ft³

Use: Outdoor projects, closets

Douglas Fir

Density: 32-37 lb/ft³

Use: Structural framing

Mahogany

Density: 36-42 lb/ft³

Use: Boatbuilding, furniture

Government Resources & Standards

USDA Forest Service

Official forestry research, lumber standards, and timber management guidelines from the United States Department of Agriculture.

NIST Measurements

National Institute of Standards and Technology provides official measurement standards and conversion factors for lumber.

Forest Products Lab

USDA Forest Products Laboratory: Research on wood properties, lumber grading, and sustainable forestry practices.

Frequently Asked Questions

How many board feet are in a 2x4x8?

An 8-foot long 2×4 contains approximately 5.33 board feet. Using actual dimensions (1.5" × 3.5" × 96"), the calculation is: (96 × 3.5 × 1.5) ÷ 144 = 5.33 BF.

What is the difference between linear feet and board feet?

Linear feet measures only length, while board feet accounts for length, width, and thickness (volume). A 10-foot 2×4 and a 10-foot 2×12 both have 10 linear feet, but the 2×12 has significantly more board feet due to its greater width.

How do lumber yards price wood?

Dimensional softwood lumber is often priced per linear foot or per piece, while hardwood lumber is typically priced per board foot. Prices vary based on wood species, grade, moisture content, and market conditions.

What is rough-sawn lumber vs. dressed lumber?

Rough-sawn lumber comes directly from the sawmill with rough surfaces and is sold at full nominal dimensions. Dressed (surfaced) lumber has been planed smooth and is smaller than its nominal size. For board feet calculations, always use actual measurements.

How accurate do my measurements need to be?

For purchasing lumber, measurements should be accurate to 1/16 inch. Professional woodworkers and lumber graders follow NHLA (National Hardwood Lumber Association) standards for consistent measurement and pricing.

Complete Guide to Lumber Measurement & Wood Calculations

Lumber Volume Calculations

Lumber Calculator Tools

Professional lumber calculators help contractors, woodworkers, and DIY enthusiasts accurately estimate material needs for construction and woodworking projects. Our wood volume calculator uses industry-standard formulas to convert dimensional measurements into board feet, ensuring precise material ordering and cost estimation.

Cubic Feet Conversion

Converting between cubic feet and board feet is essential for bulk lumber purchases. One cubic foot equals 12 board feet, allowing you to easily calculate large volume orders for commercial construction, timber framing, and wholesale lumber purchases from sawmills.

Linear Feet to Board Feet

Understanding the difference between linear feet and board feet prevents costly ordering mistakes. Linear feet measures only length, while board feet accounts for width and thickness. A 2×4 and 2×12 of the same length have identical linear feet but vastly different board feet values.

Lumber Cost Estimator

Lumber cost estimation requires accurate board feet calculations multiplied by current market prices. Hardwood is typically priced per board foot, while dimensional softwood may be priced per piece or linear foot. Always verify pricing method before ordering.

Timber Measurement Standards

Timber measurement and sawmill measurement standards ensure consistency across the forest products industry. The International Log Rule, Doyle Rule, and Scribner Rule are common scaling methods used to estimate board feet yield from standing timber or logs. Professional lumber graders follow National Hardwood Lumber Association (NHLA) standards for hardwood grading, categorizing lumber into FAS (Firsts and Seconds), Select, and Common grades based on clear face cuttings.

Dimensional lumber sizing follows standardized nominal dimensions established by industry associations. Understanding nominal vs actual dimensions is critical for accurate calculations—a nominal 2×4 actually measures 1.5" × 3.5" after planing and drying. Rough lumber dimensions are closer to nominal size, while surfaced lumber (S2S or S4S) has been planed smooth on two or four sides, reducing final dimensions.

Wood Species & Applications

Softwood Lumber

Pine lumber, Douglas Fir, and spruce dominate the framing lumber market. These softwoods offer excellent strength-to-weight ratios for structural applications.

Common uses: Construction framing, decking lumber, pressure treated wood

Hardwood Species

Oak lumber, maple lumber, walnut lumber, cherry wood, and mahogany lumber are prized for fine woodworking.

Common uses: Furniture making, cabinetry wood, flooring, millwork

Specialty Lumber

Cedar lumber resists rot naturally, making it ideal for outdoor projects. Quarter sawn oak and rift sawn lumber offer superior stability.

Common uses: Outdoor furniture, siding, closet lining, premium millwork

Project Planning & Material Selection

Woodworking Projects

Successful woodworking materials selection begins with accurate board feet calculations. Furniture making requires careful consideration of wood species density, grain patterns, and workability. Cabinetry wood should be stable, with minimal movement during seasonal humidity changes.

Understanding wood species density helps predict weight, durability, and machining characteristics. Dense hardwoods like oak and maple resist denting but require sharp tools and more cutting power.

Construction Materials

Construction materials ordering requires precise board feet calculations to minimize waste and control costs. Decking lumber calculations must account for board spacing, waste from cutting, and end trimming. Pressure treated wood is essential for ground contact applications.

Professional carpentry measurements follow building codes and industry standards. Use our building materials calculator and wood project calculator to ensure accurate material estimates.

Lumber Yard & Purchasing Guide

Lumber yard pricing varies by region, species, grade, and market conditions. Understanding how to calculate board feet allows you to compare prices across suppliers effectively. Hardwood specialty dealers typically price by board foot, while big box stores may price dimensional softwood by the piece.

Retail Lumber Yards

Mixed pricing—softwood by piece, hardwood by board foot. Expect 15-30% markup over wholesale.

Wholesale Suppliers

Bulk purchases by board foot. May require minimum order quantities. Best for contractors.

Direct from Sawmills

Rough-sawn lumber priced by board foot. Lowest cost but requires additional milling and drying time.

Advanced Lumber Terminology

Quarter Sawn Lumber

Quarter sawn lumber is cut perpendicular to the growth rings, producing exceptional stability and distinctive ray fleck patterns in species like oak. More expensive than plain sawn due to lower yield per log.

Forest Products Industry

The forest products sector includes sawmills, lumber manufacturers, and distributors. Sustainable forestry practices ensure long-term timber availability while protecting ecosystems.

Surfaced vs Rough Lumber

Surfaced lumber (S2S/S4S) is planed smooth, while rough lumber retains saw marks. Rough lumber costs less but requires thickness planing to final dimensions.

Hardwood Board Feet

Hardwood board feet calculations use actual measurements, not nominal sizes. Hardwood thickness is often expressed in quarters (4/4, 5/4, 6/4, 8/4) representing inches.