Free · Lumber & framing

Lumber Board Feet & Cost Calculator

Calculate board-foot volume from lumber dimensions and quantity.

  • Formula & worked example
  • Private in your browser
  • No signup
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Calculator inputs

Enter the values you know

Results update as you type. Edit a result to calculate another value, or lock a value to keep it fixed.

Enter feet / inches as major:minor (for example 5:10).
board feet
Cost
 / board foot
Result

Your calculation

Enter enough known values to calculate the blanks.

Use one currency for your figures. Mixed-currency conversions use rates captured October 5, 2026, rather than live exchange rates.

How to use this calculator

  1. Enter the values you know in the units shown. Leave unknown values blank.
  2. Results update automatically as you type. Edit a result to calculate another value, or lock a value to keep it fixed.
  3. Reset restores the starting fields. A worked example appears below.

Private by default

Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.

Formula and method

One board foot is a volume of 144 cubic inches. Use actual measured dimensions when estimating physical volume, and check which dimension convention your supplier uses for pricing.

Board feet = thickness(in) × width(in) × length(ft) × count ÷ 12

Worked example

Enter these known values and leave the other values blank.

Number of boards
1
Thickness
1 in
Width
12 in
Length
8:0 ft / in
Price
4 USD  / board foot
Total
8 board feet
Total cost
32 USD

Assumptions and limitations

  • Inputs must satisfy the validation rules. Editing a result can recalculate an earlier input; lock values you want to keep fixed.
  • Currency conversions use the captured source rates from October 5, 2026; they are not live exchange rates.

Common questions

What does this board foot calculation tell me?

One board foot is a volume of 144 cubic inches. Use actual measured dimensions when estimating physical volume, and check which dimension convention your supplier uses for pricing.

Can I calculate a different unknown?

Yes. Clear that field and enter the other known values. The calculator uses the available inverse equations.

References

The calculation equations, inverse formulas, units, and input rules were imported from this source. Bookify provides the interface and equation solver.

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