Square Feet to Board Feet Calculator
Planning a project? Calculate how many board feet of lumber you need to buy to cover a specific area. Enter your square footage and wood thickness.
Square Feet to Board Feet Calculator
How this calculator works:
- Board feet = Square feet × Thickness (inches)
- Pro Tip: Add 10-15% to your total for cuts and waste
- 1 board foot = volume of wood 1 foot × 1 foot × 1 inch
Convert Square Feet to Board Feet
Why Use Our Square Feet to Board Feet Calculator?
Professional lumber calculations for accurate project planning
Accurate Material Estimation
Get precise board feet calculations based on your project's square footage and lumber thickness, ensuring you purchase exactly what you need.
Waste Factor Included
Our calculator includes an adjustable waste factor (5-25%) to account for cutting waste, defects, and installation errors.
Common Thickness Presets
Choose from standard lumber thicknesses (1/4", 1/2", 3/4", 1") or enter custom thickness for specialty materials.
Project Planning Tool
Perfect for flooring, siding, paneling, and decking projects where you know the area to be covered but need to determine lumber quantity.
Cost Saving
Avoid over-purchasing expensive lumber or the costly delays of under-ordering by calculating your exact material needs.
How to Use the Square Feet to Board Feet Calculator
Simple steps to determine your lumber needs
Enter Your Area
Input the square footage of the area you need to cover with lumber.
Select Lumber Thickness
Choose from common thicknesses or enter a custom thickness in inches.
Add Waste Allowance
Toggle the waste allowance option and adjust the percentage based on your project complexity.
Get Your Results
Instantly see how many board feet of lumber you'll need to purchase for your project.
Calculator Parameters
Understanding inputs for accurate square feet to board feet conversions
Square Feet
The area you need to cover with lumber
Lumber Thickness
The actual thickness of your lumber
Waste Percentage
Additional material to account for waste
Square Feet to Board Feet Conversion Formula
The mathematical relationship between area and lumber volume
Basic Formula
The fundamental formula for converting area to lumber volume
Board Feet = Square Feet × Thickness (inches) Example: 100 sq ft × 0.75" = 75 board feet
With Waste Factor
Formula including waste allowance for realistic ordering
Total Board Feet = (Square Feet × Thickness) × (1 + Waste%) Example: 75 board feet × 1.15 = 86.25 board feet (with 15% waste)
Calculation Examples
Real-world examples of square feet to board feet conversions
Hardwood Flooring Project
Calculating board feet needed for a bedroom floor
Calculation steps
Wall Paneling Project
Determining lumber for accent wall paneling
Calculation steps
Deck Building Project
Estimating decking material requirements
Calculation steps
Understanding Your Results
Small Projects (Under 100 sq ft)
For small areas like accent walls or small rooms, expect to need between 25-100 board feet depending on thickness.
Medium Projects (100-300 sq ft)
Medium-sized projects like average rooms or small decks typically require 75-450 board feet based on lumber thickness.
Large Projects (Over 300 sq ft)
Large areas like full floors or large decks may need 225+ board feet, making accurate calculations especially important for cost control.
Frequently Asked Questions
Common questions about square feet to board feet conversion
Square feet is a measure of area (length × width), while board feet is a measure of volume (length × width × thickness). Square feet tells you how much surface area you need to cover, while board feet tells you how much wood volume you need to purchase.
To convert square feet to board feet, multiply the square footage by the thickness of the lumber in inches. For example, 100 square feet of area covered with 3/4-inch thick lumber requires 75 board feet of lumber (100 × 0.75 = 75).
Adding a waste allowance (typically 10-15%) accounts for material lost during cutting, boards with defects, installation mistakes, and complex fitting requirements. This ensures you purchase enough material to complete your project without running short.
The cost per board foot varies widely depending on wood species, grade, and market conditions. Common construction lumber might cost $2-5 per board foot, while exotic hardwoods can cost $10-30+ per board foot. Check with your local lumber supplier for current pricing.
Yes, this calculator works for any wood product where you know the thickness and the square footage to be covered, including engineered wood products like plywood, OSB, or engineered flooring.
For 100 square feet of flooring with 3/4-inch thick boards (standard hardwood flooring thickness), you would need 75 board feet of lumber. With a 15% waste allowance, you should purchase about 86 board feet.
Calculator Disclaimer
This square feet to board feet calculator provides estimates for planning purposes only. Please note:
1. Actual material needs may vary based on installation methods and project specifics
2. Always verify lumber dimensions - nominal sizes differ from actual dimensions
3. Waste factors vary by project complexity, installer experience, and lumber quality
4. For critical projects, consult with professional contractors or lumber suppliers