Calculating your total board feet is straightforward once you know the Board Feet formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the Board Feet Calculator.
What is Board Feet?
The Board Feet calculation tells you your total board feet from a few simple inputs. The figure you are solving for here is the total board feet.
The Board Feet formula
The core formula is:
Total board feet = Thickness × Width × Length ÷ 12 × Number of boardsHere is what each input means:
- Thickness — a value measured in in. Example: 1 in.
- Width — a value measured in in. Example: 6 in.
- Length — a value measured in ft. Example: 8 ft.
- Number of boards — a number. Example: 1.
How to calculate it step by step
- Write down the thickness (for example, 1 in).
- Write down the width (for example, 6 in).
- Write down the length (for example, 8 ft).
- Write down the number of boards (for example, 1).
- Apply the formula above to get your total board feet.
- Double-check the result with the Board Feet Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Thickness | 1 in |
| Width | 6 in |
| Length | 8 ft |
| Number of boards | 1 |
| Total board feet | 4.00 |
| Board feet per board | 4.00 |
With thickness of 1 in, width of 6 in, length of 8 ft and number of boards of 1, the total board feet works out to 4.00.
Example 2
With thickness of 2 in, width of 6 in, length of 8 ft and number of boards of 1, the total board feet works out to 8.00.
| Result | Value |
|---|---|
| Total board feet | 8.00 |
| Board feet per board | 8.00 |
Example 3
With thickness of 5 in, width of 6 in, length of 8 ft and number of boards of 1, the total board feet works out to 20.00.
| Result | Value |
|---|---|
| Total board feet | 20.00 |
| Board feet per board | 20.00 |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
Prefer not to do the maths by hand? — the Board Feet Calculator does it instantly, for free, with the formula and a worked example built in.
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