What thickness should I enter for 4/4, 5/4, 6/4, or 8/4 lumber?

Use the thickness your supplier uses on the tally or quote. In this calculator, 4/4 is entered as 1 inch. For 5/4, multiply the 1-inch factor by 1.25, or enter 1.25 inches.

How do I convert board feet back to linear feet?

Use the board feet to linear feet calculator. That page is built for BF → LF; this page only turns a known length into board feet.

Linear Feet to Board Feet Calculator

LF to BF — Free Lumber Conversion

Enter length in linear feet plus thickness and width. Wrong size in means the wrong board feet out.

Length (linear feet)

The board's length in linear feet (LF).

Pieces

How many boards of this size. Leave 1 for a single board.

Thickness (inches)

Use nominal inches. Example: 4/4 lumber is about 1 inch.

Width (inches)

Use nominal inches. Example: a 2×4 is entered as width 4.

Quick Size

Tap a common size to auto-fill thickness and width.

Board Feet

5.33 BF

= 0.67 BF per linear foot

Uses nominal dimensions — the lumber-trade convention for board feet. Estimate only; confirm totals with your supplier.

Price ($ per linear foot)

$/LF

Optional. Enter the quoted price per linear foot to estimate total cost.

Estimated total cost

—

Optional. Enter the quoted price per linear foot to estimate total cost.

Need board feet to linear feet instead? Use the Board Feet to Linear Feet Calculator.

What does this 5.33 BF mean?

It is the volume of the size you typed — 8 linear feet of a 2×4. Each foot of that 2×4 holds 0.67 board feet, so 8 × 0.67 = 5.33 BF. It is not a board count, and it is not an order.

Linear feet measure length only. Board feet measure volume. Thickness and width connect them, so a yard's length quote becomes wood you can compare.

If you typed different dimensions than the quote, this number is for the wrong board. A $/LF price is not a $/BF price, and this page is not the supplier's tally.

Before you treat this as an order:

Match thickness and width to the supplier's tally — a nominal 2×4 and a dressed 1.5″ × 3.5″ convert differently
This result is volume for that run of length, not how many stock boards to buy
Confirm totals with the yard before you order

Linear feet to board feet formula

This is the math the calculator uses. Thickness and width are nominal inches. Length is in feet.

Board Feet = (Thickness × Width ÷ 12) × Linear Feet

Thickness × width ÷ 12 is board feet per linear foot. A 2×6 or 1×12 equals 1, so linear feet and board feet match one-to-one.

8 ft 2×4: (2 × 4 ÷ 12) × 8 = 5.33 BF.
60 linear feet of 2×6: (2 × 6 ÷ 12) × 60 = 60 BF.

Linear Feet to Board Feet Conversion Chart

BF per linear foot factors and board feet at common lengths, based on the WWPA board measure equivalents.

Nominal Size	BF per LF	8 ft	10 ft	12 ft	16 ft
1×2	0.1667	1.33BF	1.67BF	2.00BF	2.67BF
1×4	0.3333	2.67BF	3.33BF	4.00BF	5.33BF
1×6	0.50	4.00BF	5.00BF	6.00BF	8.00BF
1×8	0.6667	5.33BF	6.67BF	8.00BF	10.67BF
1×10	0.8333	6.67BF	8.33BF	10.00BF	13.33BF
1×12	1.00	8.00BF	10.00BF	12.00BF	16.00BF
2×4	0.6667	5.33BF	6.67BF	8.00BF	10.67BF
2×6	1.00	8.00BF	10.00BF	12.00BF	16.00BF
2×8	1.3333	10.67BF	13.33BF	16.00BF	21.33BF
2×10	1.6667	13.33BF	16.67BF	20.00BF	26.67BF
2×12	2.00	16.00BF	20.00BF	24.00BF	32.00BF

5/4 (five-quarter) boards: multiply the 1-inch factor by 1.25.

Source: Western Wood Products Association (WWPA) Board Measure Equivalents. Checked 2026-06-12.

Tip: tap a row or column to highlight it. Sizes where thickness × width = 12 (like 2×6 and 1×12) convert one-to-one.

Common Mistakes to Avoid

These details cause most LF → BF errors.

Treating linear feet and board feet as interchangeable

They measure different things — length vs volume. 100 linear feet of 2×12 is 200 board feet, while 100 linear feet of 1×4 is only 33 board feet. Always convert before comparing quantities or prices.

Using actual size instead of nominal size

A 2×4 really measures about 1.5 × 3.5 inches, but board feet are calculated on the nominal 2 × 4 by trade convention. Enter nominal sizes here unless your supplier explicitly measures by actual dimensions.

Comparing a $/LF quote directly with a $/BF price

Convert first: $ per board foot = $ per linear foot ÷ the BF-per-LF factor. A 2×4 at $1.00 per linear foot is $1.50 per board foot, since each foot of length is only 0.67 BF.

When should you use a different page?

I have board feet and need length

Flip the conversion when the tally is already in board feet and you need linear feet for that size.

Board Feet to Linear Feet Calculator

The quote is in thousand board feet

MBF is 1,000 board feet. Convert the mill quote to length on the MBF page.

MBF to Linear Feet Calculator

I need coverage area, not volume

Square feet measure area. That is a different conversion than board feet.

Board feet vs square feet vs linear feet

I am measuring a log, not a board

Log scale uses Doyle, Scribner, or International — not this length-to-volume formula.

Log Board Foot Calculator

❓

Frequently Asked Questions

Yes. Lineal feet is the older trade spelling — the WWPA conversion tables use lineal — but it means exactly the same thing as linear feet.

Need the reverse direction?Board Feet to Linear Feet Calculator

Disclaimer

Calculations use nominal dimensions, the lumber-trade convention for board feet. Results are estimates for planning. Always confirm quantities and pricing with your supplier before ordering.

Last updated: 2026-06-12

Sources

Western Wood Products Association (WWPA): Board Measure Equivalents table (lineal feet to board feet factors)
Curtis Lumber: Board Footage Chart (formula cross-check)