🪵 Lumber Calculator
Board feet, framing materials, decking, and dimensional lumber estimation
Board Feet Calculator
Wall Framing Calculator
Deck Lumber Calculator
Small Deck (10x10)
Medium Deck (12x12)
Large Deck (16x20)
Dimensional Lumber Calculator
Lumber Calculation Results
Total Board Feet
133.3
bd ft
Total Linear Feet
80
lin ft
Total Pieces
10
boards
Estimated Cost
$166.67
USD
| Item | Dimension | Length | Qty | Board Feet | Cost |
|---|---|---|---|---|---|
| Lumber | 2x4 | 8' | 10 | 53.3 | $66.67 |
Material Cost: $166.67 | Cost per Board Foot: $1.25
📏 Lumber Size Reference (Nominal vs Actual)
| Nominal Size | Actual Dimensions | Common Uses | Board Feet per Linear Foot |
|---|---|---|---|
| 1x4 | 3/4" × 3.5" | Furring, shelving | 0.33 |
| 1x6 | 3/4" × 5.5" | Fencing, trim | 0.50 |
| 2x4 | 1.5" × 3.5" | Wall studs, framing | 0.67 |
| 2x6 | 1.5" × 5.5" | Deck joists, rafters | 1.00 |
| 2x8 | 1.5" × 7.25" | Floor joists, beams | 1.33 |
| 2x10 | 1.5" × 9.25" | Headers, large beams | 1.67 |
| 2x12 | 1.5" × 11.25" | Stair stringers, rafters | 2.00 |
| 4x4 | 3.5" × 3.5" | Deck posts, fencing | 1.67 |
| 4x6 | 3.5" × 5.5" | Beams, heavy posts | 2.33 |
| 6x6 | 5.5" × 5.5" | Heavy posts, columns | 4.00 |
Frequently Asked Questions
How do you calculate board feet?
Board feet = (Thickness in inches × Width in inches × Length in feet) ÷ 12. For example, a 2x4x10 board = (2 × 4 × 10) ÷ 12 = 6.67 board feet.
How many 2x4 do I need for a wall?
For a standard wall, studs are spaced 16 inches on center. Divide wall length in feet by 1.33, add 1 for the end. For a 20ft wall: 20 ÷ 1.33 = 15 + 1 = 16 studs. Double for top and bottom plates.
What is the difference between nominal and actual lumber sizes?
Nominal size is the rough-sawn dimension (2x4). Actual size is after drying and planing: 2x4 = 1.5" × 3.5", 2x6 = 1.5" × 5.5", 4x4 = 3.5" × 3.5".
How much does lumber cost?
Lumber prices vary by species and grade. Pressure-treated pine: $0.50-$1.50 per board foot. Cedar: $1.50-$4.00. Oak: $3.00-$8.00. Douglas fir: $1.00-$2.50.
How do I calculate lumber for a deck?
Calculate decking: (Deck width ÷ board width) × deck length × 1.1 for waste. For joists: (Deck length ÷ joist spacing) × deck width. Posts: every 6-8 feet.