Wood Board Calculator
How many boards of a given size you need to cover an area, or to yield a run of a given length.
At a glance
- What you enter
- What are you measuring?, Area to cover, Total linear run, Board width (dressed), Board length, Board thickness (dressed), Gap between boards, Waste allowance
- What you get
- Boards to buy, Total linear feet, Total area covered, Total board feet
- Formula shown
- Yes, every step, right below your results.
- Cost and privacy
- Free, no account needed, and nothing you type is stored.
See worked examples ↓ Read the FAQ ↓ Share this calculator ↓
Results are estimates for general information only, always verify with a professional or official source before acting on them.
How to use the Wood Board Calculator
- 1 Enter What are you measuring?
- 2 Enter Area to cover (sq ft), Used in area mode. Length times width of the surface.
- 3 Enter Total linear run (ft), Used in linear mode. The distance the boards have to fill.
- 4 Enter Board width (dressed) (in), A nominal 1x6 is 5.5 inches dressed. Use 3.5 for a 1x4 and 7.25 for a 1x8.
- 5 Enter Board length (ft)
- 6 Enter Board thickness (dressed) (in), Used for the volume and board feet figures. A nominal 1x is 0.75 inches.
- 7 Enter Gap between boards (in), Leave at zero for a closed surface such as a shelf or a floor of tongue and groove.
- 8 Enter Waste allowance (%)
- 9 Press Calculate. You get Boards to buy, Total linear feet, Total area covered, Total board feet, and every intermediate step stays visible under "How is this calculated?"
- 10 Change one number at a time to see what moves the result, that is usually the most useful thing a calculator can tell you.
Worked examples
Real numbers run through this calculator. Open any example to load it into the form above and change it.
Deck in 5/4 by 6 decking
120 square feet of deck covered with 12 foot boards at a quarter inch gap.
You enter
- What are you measuring?
- 1
- Area to cover
- 120 sq ft
- Board width (dressed)
- 5.50 in
- Board length
- 12 ft
- Board thickness (dressed)
- 1 in
- Gap between boards
- 0.25 in
- Waste allowance
- 10%
You get
- Boards to buy
- 24
- Total linear feet
- 288.00 ft
- Total area covered
- 138.00 sq ft
- Total board feet
- 132.00 bf
Each board covers 5.75 square feet at that gap.
Linear fence rails
48 feet of fence needing two rails, so 96 linear feet of 12 foot boards.
You enter
- What are you measuring?
- 2
- Area to cover
- 28 sq ft
- Total linear run
- 96 ft
- Board width (dressed)
- 3.50 in
- Board length
- 12 ft
- Board thickness (dressed)
- 1.50 in
- Gap between boards
- 0 in
- Waste allowance
- 10%
You get
- Boards to buy
- 9
- Total linear feet
- 108.00 ft
- Total area covered
- 31.50 sq ft
- Total board feet
- 47.25 bf
Eight boards before waste, nine after.
Shelf boards for a pantry
A pantry needing 40 square feet of shelving in 1x10 at 8 feet.
You enter
- What are you measuring?
- 1
- Area to cover
- 40 sq ft
- Board width (dressed)
- 9.25 in
- Board length
- 8 ft
- Board thickness (dressed)
- 0.75 in
- Gap between boards
- 0 in
- Waste allowance
- 10%
You get
- Boards to buy
- 8
- Total linear feet
- 64.00 ft
- Total area covered
- 49.33 sq ft
- Total board feet
- 37.00 bf
A 1x10 is 9.25 inches dressed, so each 8 foot shelf covers 6.17 square feet.
Guides that go with it
How to Measure Wood Correctly for DIY Handcraft Projects
You bought a board, measured twice, cut once, and it still came up short. Or worse, the "1 x 6" you ordered arrived looking nothing like an inch thick or six inches wide. If that sounds familiar, the...
Wood Calculator Guide: Calculate Lumber, Board Feet, Cabinet Materials & Project Costs
A wood calculator turns a vague "how much do I need?" into a number you can hand to a lumber yard. By the end of this guide you will be able to measure a project, convert odd dimensions into board fee...
Hardwood vs Softwood: What's the Difference and Which Wood Should You Choose?
You're standing in the lumber aisle or scrolling a supplier's site trying to decide between two boards that look similar but carry very different price tags. One is labelled hardwood, the other softwo...
Frequently asked questions
How many deck boards do I need for 120 square feet?
Do I calculate with nominal or actual board width?
How much waste should I add for a deck?
Should I leave a gap between deck boards?
Terms used here
Short, plain-language definitions of the words this calculator uses.