Title: Board foot calculator | Cercha
Description: Calculate board feet from thickness, width, length, and piece count. Check nominal or measured dimensions before comparing a lumber tally.
Canonical: https://cercha.pages.dev/tools/board-foot-calculator/
# Board foot calculator
Construction calculators
Turn a measured or quoted lumber list into board feet without changing its dimension basis.
You have a lumber list from the crew or a supplier tally to check before purchasing. Enter thickness and width in inches, length in feet, and the number of identical boards. The calculator returns board feet per piece and for the full group.
## Keep the dimension basis visible
Choose the label for nominal tally dimensions or measured dimensions. The label records your basis; it does not change the numbers. If you measure the boards on site, enter those measurements directly. If you check a quoted tally, use the dimensions on that tally and confirm the basis with the supplier.
Keep different sizes and lengths in separate runs. Write the stock description beside each result before adding the group totals. This makes a comparison traceable when one line uses a different thickness or piece count.
## Use inches, inches, then feet
The [Wood-Mizer board-foot formula](https://woodmizer.com/us/learning-center/what-is-a-board-foot) multiplies thickness in inches by width in inches by length in feet, then divides by twelve. Multiply that per-piece volume by the piece count. This calculator follows that formula and multiplies before rounding.
For example, entered dimensions of one inch by six inches by eight feet give four board feet per piece. Twelve identical boards total forty-eight board feet. This example describes the entered dimensions, not a conversion from a nominal stock label.
Calculate the group total before rounding. Multiplying a rounded per-piece display can change your comparison with the supplier’s tally.
## Keep the cut list beside the volume
There is no automatic allowance for waste. Decide which extra pieces belong in the lumber list before using its count here. Keep cut lengths, stock sizes, and any rejected pieces visible instead of treating the volume total as a purchasing list.
The tool does not choose lumber grade or member size. It also does not convert a log into expected usable boards. Confirm the supplier’s tally and billing conventions before using the result to compare prices.
## Check the inputs and results
| Input | Unit and accepted values |
| --- | --- |
| Thickness and width | Inches, 0.000001 through 1,200 |
| Length | Feet, 0.000001 through 10,000 |
| Identical pieces | Whole count, 1 through 100,000 |
| Dimension-basis label | Nominal tally or measured dimensions; no automatic conversion |
Enter ordinary decimal dimensions and a whole piece count. The tool calculates the group total before rounding the display. It adds no waste allowance.
## Before you order lumber
Keep the quantity unit on the order. [NIST’s conversion table](https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/nist-guide-si-appendix-b8) lists board foot separately from other volume units. The entered dimensions determine this calculation.
Use [APA’s framing reference](https://www.apawood.org/applications-systems/fully-sheathed-wall-systems/advanced-framing/) to discuss the specified assembly, and [APA’s engineered-wood guidance](https://dinosaur.apawood.org/spring-2022-designers-circle) for alteration questions. Board feet do not approve a member or a cut.
Match the material description to the [supplier’s lumber package](https://www.bldr.com/products/lumber). Ask the [framing sub](/trades/framing/) to check the cut list before discussing the tally with the [lumber supplier](/suppliers/lumber/).
Keep inspection release separate from volume. [Raleigh’s inspection sequence](https://raleighnc.gov/permits/services/residential-inspections) identifies the framing checkpoint. Use the [framing inspection guide](/guides/framing-inspection/) when assigning the review.
Return to the [construction tools hub](/tools/) for the other quantity checks and printable records.
## Where Cercha fits
Supplier profiles in the Cercha app list brands carried. Use Messages to discuss the stock description and quantity basis with a supplier. Keep the board-foot calculation beside the lumber list you are discussing.
- Thickness (in): 2
- Width (in): 4
- Length (ft): 8
- Identical pieces (count): 1
Dimensions entered as: nominal tally dimensions (change this label on the HTML page).
Per piece (BF): 5.333333; Total (BF): 5.333333; Estimated board feet (BF): 5.333
## How this is calculated
Board feet per piece = thickness (in) × width (in) × length (ft) ÷ 12. Total board feet = board feet per piece × pieces.
T and W are entered inches, L is feet, and q is identical boards. Multiply all pieces before rounding.
Per-piece and total volumes show six decimal places. The main estimate shows three. Multiply before rounding; no purchase ceiling is applied.
Ordinary displays round half up: an exact halfway value rounds upward. Display rounding never changes the purchase ceiling.
[Wood-Mizer: What is a Board Foot?](https://woodmizer.com/us/learning-center/what-is-a-board-foot). Thickness inches times width inches times length feet divided by 12, multiplied by pieces; 5/4 thickness = 1.25 inches.
Estimate only. Use the entered nominal tally or measured dimensions consistently. No nominal-size conversion is applied. Confirm supplier tally and billing conventions. This is not a log-yield estimate.
Estimate only. No structural sizing, loads, spans, strengths, or code-compliance decisions are calculated.
Lumber volume estimate only. The tool uses entered dimensions without nominal-size conversion or an automatic waste allowance.
Print this calculator from the HTML page.
## Build your connections
[Ask about the beta]()
## Sources
1. Wood-Mizer. (2020, February 19). *What is a Board Foot?* https://woodmizer.com/us/learning-center/what-is-a-board-foot
2. NIST. (2025, August 18). *Guide to the SI, Appendix B.8*. https://www.nist.gov/pml/special-publication-811/nist-guide-si-appendix-b-conversion-factors/nist-guide-si-appendix-b8
3. APA: The Engineered Wood Association. (n.d.). *Advanced Framing*. Retrieved October 14, 2026, from https://www.apawood.org/applications-systems/fully-sheathed-wall-systems/advanced-framing/
4. APA - The Engineered Wood Association. (2022). Spring 2022 Designers Circle. *APA*. https://dinosaur.apawood.org/spring-2022-designers-circle
5. Builders FirstSource. (n.d.). *Framing Lumber, Boards, and Bracing*. Retrieved October 14, 2026, from https://www.bldr.com/products/lumber
6. City of Raleigh. (2026, October 12). *Residential Inspections*. Raleighnc.gov. https://raleighnc.gov/permits/services/residential-inspections