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Lumber & Material

Linear Feet ↔ Board Feet Converter

Translate between running feet of a known cross-section and board feet — useful for trim, decking, and 2× lumber.

Calculator

What makes this different

Most converters assume a single standard cross-section. This one lets you pick common nominal sizes (1×2, 2×4, 2×6 …) or enter a custom cross-section, and shows the formula. It also handles the actual (not nominal) dimensions after surfacing.

Who it's for & when to use it

Ordering baseboard, crown, or 2×4 framing; comparing per-linear-foot quotes to per-BF quotes.

How to use

  1. Enter the dimensions of your material or the parameters of your project.
  2. Adjust the optional knobs (waste factor, kerf, planer allowance) to match your shop practice.
  3. Click Calculate and read the output. Use the per-item breakdown for ordering, the totals for budgeting.
  4. Compare the result to your lumber yard's quote — the effective $/BF column is the apples-to-apples number.

Formula: BF = LF × (actual_t × actual_w) / 144. Nominal dimensions shown for reference; actual dimensions are used for the math.

Notes & tips from the shop

  • A 2×4 is not 2 in × 4 in. Surfaced it is 1.5 × 3.5 in. That difference adds up across 100 linear feet.
  • Linear feet is a length, board feet is a volume. You cannot convert without knowing the cross-section.
  • Trim is usually sold per LF, structural lumber per BF or per piece.

Frequently asked questions

Is 8 ft of 2×4 really 5.33 BF?

Yes — 1.5 × 3.5 × 96 in / 144 in³/BF = 3.5 BF per 8 ft stick. A 2×4 stud is normally 92-5/8 in or 96 in. Use the actual length you order.

Can I mix nominal and actual dimensions?

You can, but the answer will be misleading. Always use actual dimensions for purchased material.

Why do I get a different answer than the lumber yard?

Yards may round to whole BF per piece. Always buy at least one extra piece for offcuts and mistakes.

Limitations

Linear feet of a single cross-section only. Compound cross-sections or tapered boards not supported.

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