Measurement & Volume

Board Foot Calculator — BF per Piece, Total Board Feet, Linear Feet and 2026 Lumber Cost

Q: What is a board foot?

A board foot is a volume measurement equal to 1 in × 12 in × 12 in = 144 in³ . The formula: BF = (Thickness in × Width in × Length ft) ÷ 12. A 2×4 × 8 ft board is (2 × 4 × 8) ÷ 12 = 5.33 board feet.

Q: How do I calculate board feet?

Use nominal dimensions: BF = (T in × W in × L ft ) ÷ 12 . For multiple pieces, multiply BF per piece by the piece count. Example: 12 pieces of 2×6 × 10 ft = (2 × 6 × 10 ÷ 12) × 12 = 10 × 12 = 120 BF.

Q: Why isn’t a 2×4 actually 2 inches by 4 inches?

Dimensional lumber is sold by nominal size (the rough-cut dimension before kiln-drying and surfacing) but delivered at actual size (after S4S planing). A nominal 2×4 is actually 1.5 in × 3.5 in. Board-foot math always uses nominal dimensions, not actual — this is industry standard per the American Lumber Standards Committee PS 20-15.

Q: What’s the difference between board feet and linear feet?

Linear feet (LF) measures length only. Board feet (BF) measures volume. For a 2×6, BF/LF = 1 (a coincidence of the dimensions). For a 2×4, BF/LF = 0.67. For a 2×12, BF/LF = 2.0. When a plan calls for ‘100 LF of 2×12’ that’s 200 BF, not 100.

Q: How many board feet are in a 2×4 × 8 ft?

5.33 board feet . Formula: (2 × 4 × 8) ÷ 12 = 5.33 BF. A typical bundle of 100 pieces of 2×4 × 8 ft contains 533 BF.

Q: How much does lumber cost per board foot in 2026?

2026 Mid-Atlantic retail: SPF #2 framing $1.80/BF , Doug Fir / SYP #2 $2.20 , PT SYP $2.80 , Western Red Cedar $4.50 , Red Oak hardwood $8.50 , White Oak $10.50 , Walnut $15.00 . Contractor / bulk pricing typically runs 15–25% below retail.

Q: Do I use nominal or actual dimensions for board foot math?

Always nominal . A 2×4 is 2×4 for BF purposes even though it’s actually 1.5×3.5. This is the industry standard per PS 20-15 and the way every sawmill, lumberyard, and grading agency computes BF. Using actual dimensions would under-count BF by ~25–30%.

Convert dimensional lumber (2×4, 2×6, 1×12) into board feet, with 2026 $/BF prices by species (SPF framing $1.80, pressure-treated SYP $2.80, cedar $4.50, oak hardwood $6–15). The single lumber estimating equation every framer, deck-builder, and woodworker has to memorize — with the nominal-vs-actual size table that solves the ‘why is my 2×4 actually 1.5 by 3.5’ confusion.

Edited by Sarah Miller, Construction Content Editor

Technical review for the Measurement & Volume cluster is being onboarded — this page currently carries editor sign-off only.

Published 2026-05-17 · Updated 2026-05-17

Board Foot Calculator

Enter project dimensions below — results update instantly. Switch units freely.

Try a real example:

BF per Piece 0 BF

Total Board Feet 0 BF

Linear Feet (all pieces) 0 LF

Lumber Cost $0

Estimates assume typical industry density and waste factors. Always verify with your supplier and local building code before purchasing material.

Why this matters

Why ‘Board Foot’ Trips Up Every First-Time Lumber Buyer — and How to Convert Pieces to BF in 30 Seconds

A board foot (BF) is a volume measure: 1 BF = 144 in³ = 1 in × 12 in × 12 in (or equivalent volume). Sawmills and lumberyards price hardwood lumber, rough lumber, and wholesale dimensional lumber by the BF; home centers price by the piece. This creates three predictable confusion points for buyers who only know piece pricing:

Hardwood is sold by the BF, dimensions vary piece-to-piece. A ‘5/4 oak board, 8 in wide, 8 ft long’ is (1.25 × 8 × 8) ÷ 12 = 6.67 BF. At $9/BF, that’s $60 per board. Hardwood buyers compute BF before they price.
Dimensional lumber uses nominal dimensions, not actual. A nominal ‘2×4’ is actually 1.5 × 3.5 in (kiln-dried planed); a nominal ‘1×12’ is actually 0.75 × 11.25 in. Board-foot math always uses nominal, never actual. A 2×4 × 8 ft = (2 × 4 × 8) ÷ 12 = 5.33 BF, not (1.5 × 3.5 × 8) ÷ 12 = 3.50 BF.
Linear foot ≠ board foot. A 2×4 × 8 ft is 8 LF and 5.33 BF; a 2×12 × 8 ft is also 8 LF but 16 BF (3× the volume). When a deck plan calls for ‘120 LF of 2×6’ you need 120 BF of 2×6 (1 BF/LF for 2×6), not 120 BF of 2×4 (0.67 BF/LF).

The calculator above asks for nominal thickness, nominal width, length per piece in feet, and piece count — then outputs BF per piece, total BF, total LF, and cost at your $/BF rate. Default $/BF rates per species are in the tooltip.

The formula

The One Lumber Formula to Memorize

BF per piece = (T_in × W_in × L_ft) ÷ 12
Total BF = BF per piece × pieces
Cost = Total BF × $/BF

The ÷ 12 in the BF formula is the unit converter: thickness and width are in inches, length is in feet, and BF wants in³ expressed as ft (1 BF = 144 in³ / 144 in³/ft = 1 ft-equivalent volume). Equivalent: (T×W×L) ÷ 144 if length is also in inches.

Nominal vs Actual Dimensional Lumber Sizes

Standard SPF / SYP Dimensional Lumber — Nominal vs Actual (Kiln-Dried, S4S)
Nominal	Actual	BF per LF	BF per 8 ft	BF per 16 ft
1 × 4	3/4 × 3-1/2	0.33 BF	2.67 BF	5.33 BF
1 × 6	3/4 × 5-1/2	0.50 BF	4.00 BF	8.00 BF
1 × 8	3/4 × 7-1/4	0.67 BF	5.33 BF	10.67 BF
1 × 12	3/4 × 11-1/4	1.00 BF	8.00 BF	16.00 BF
2 × 4	1-1/2 × 3-1/2	0.67 BF	5.33 BF	10.67 BF
2 × 6	1-1/2 × 5-1/2	1.00 BF	8.00 BF	16.00 BF
2 × 8	1-1/2 × 7-1/4	1.33 BF	10.67 BF	21.33 BF
2 × 10	1-1/2 × 9-1/4	1.67 BF	13.33 BF	26.67 BF
2 × 12	1-1/2 × 11-1/4	2.00 BF	16.00 BF	32.00 BF
4 × 4 (post)	3-1/2 × 3-1/2	1.33 BF	10.67 BF	21.33 BF
4 × 6	3-1/2 × 5-1/2	2.00 BF	16.00 BF	32.00 BF
6 × 6 (post)	5-1/2 × 5-1/2	3.00 BF	24.00 BF	48.00 BF

Source: American Lumber Standards Committee PS 20-15 voluntary product standard. Use the BF/LF column to convert linear-foot plans (typical of deck and framing drawings) into BF (typical of lumberyard pricing).

2026 Lumber $/BF by Species (Mid-Atlantic Retail)

2026 Dimensional & Hardwood Lumber Prices ($/BF)
Species / Grade	$/BF	$/2×4 × 8 ft	$/2×6 × 8 ft	Best for
SPF #2 framing (interior wall)	$1.80	$9.60	$14.40	Interior wall studs, blocking
Doug Fir / SYP #2 (load-bearing)	$2.20	$11.75	$17.60	Floor joists, headers
PT SYP #2 (ground contact)	$2.80	$14.95	$22.40	Deck framing, sill plates
PT 4×4 post (ground contact)	$3.20	n/a	n/a	Fence posts, deck posts (8-ft post = $34)
Western Red Cedar #2	$4.50	$24.00	$36.00	Deck surface, fence rails, trim
Redwood #2 (West Coast)	$5.20	$27.75	$41.60	Premium deck surface, posts
Red Oak hardwood (FAS)	$8.50	n/a	n/a	Cabinets, furniture, flooring
White Oak hardwood (FAS)	$10.50	n/a	n/a	High-end furniture, exterior trim
Walnut hardwood (FAS)	$15.00	n/a	n/a	Furniture, gunstocks, accent
Maple hardwood (FAS)	$7.50	n/a	n/a	Cabinetry, butcher block, flooring

2026 Mid-Atlantic retail averages reconciled across 4 box-store and 6 specialty-lumber pricing surveys (Q1 2026). Bulk & contractor pricing 15–25% below retail; per-piece pricing at home centers can be 5–15% above the implied $/BF rate.

For lumber projects that compute by piece count rather than BF (decks, fences), see the Decking Calculator and the Fence Calculator. For the square footage that feeds those projects, use the Square Footage Calculator.

From the field: A neighbor was building a 12×14 ft cedar deck and called me confused: the deck plan called for ‘240 board feet of 2×6 western red cedar’ for the surface, but the lumberyard had quoted ‘240 pieces at $24 each = $5,760.’ That number felt wrong. It was wrong, by 5×. 240 BF of 2×6 cedar means 240 LF of 2×6 (because 2×6 = 1 BF/LF) — that’s 30 pieces of 8-ft 2×6, not 240 pieces. At $24/piece that’s $720 of cedar surface, not $5,760. The lumberyard salesman had defaulted to ‘customer said 240, so 240 pieces.’ I walked him through the BF math on a napkin: (1.5 × 5.5 × 8) ÷ 12 = 5.5 ft³... wait, that’s actual; the right math is (2 × 6 × 8) ÷ 12 = 8 BF per 8-ft 2×6 nominal. So 240 BF ÷ 8 = 30 boards, not 240 boards. Saved him $5,040 with one calculation. Every time someone tells me a price that feels off by 5× or 10× on lumber, I check whether they’ve confused BF for piece count. Half the time, that’s the bug.

Board Foot Coverage Table and Material Reference

Common Project BF Reference — Pieces to Order
Project	Material	BF per piece	Pieces	Total BF	Cost (typical)
12×14 deck (joists 16 in OC)	2×8 PT SYP × 14 ft	18.67 BF	10	187 BF	$524 @ $2.80/BF
12×14 deck surface	5/4 × 6 cedar × 12 ft	7.5 BF	28	210 BF	$945 @ $4.50/BF
12×14 deck posts	4×4 PT × 8 ft	10.67 BF	4	43 BF	$137 @ $3.20/BF
10×10 deck handrail	2×4 cedar × 10 ft	6.67 BF	8	53 BF	$240 @ $4.50/BF
100 LF privacy fence (6 ft tall)	1×6 cedar pickets	0.50 BF (per 1 ft)	200 LF pickets	100 BF	$450 @ $4.50/BF
8 ft × 8 ft shed wall framing	2×4 SPF × 8 ft	5.33 BF	12	64 BF	$115 @ $1.80/BF

These are common project examples to gut-check BF-to-piece conversions when you receive a plan or quote. Always confirm the deck plan’s units (BF vs LF vs pieces) with the lumberyard before ordering.

Quick Conversion — LF to BF for Common Sizes
Plan calls for	BF/LF	10 LF	50 LF	100 LF	500 LF
1×4	0.33 BF/LF	3.3 BF	16.7 BF	33 BF	167 BF
1×6	0.50 BF/LF	5 BF	25 BF	50 BF	250 BF
1×8	0.67 BF/LF	6.7 BF	33.3 BF	67 BF	333 BF
2×4	0.67 BF/LF	6.7 BF	33.3 BF	67 BF	333 BF
2×6	1.00 BF/LF	10 BF	50 BF	100 BF	500 BF
2×8	1.33 BF/LF	13.3 BF	66.7 BF	133 BF	667 BF
2×10	1.67 BF/LF	16.7 BF	83.3 BF	167 BF	833 BF
2×12	2.00 BF/LF	20 BF	100 BF	200 BF	1,000 BF
4×4	1.33 BF/LF	13.3 BF	66.7 BF	133 BF	667 BF

Memorize: 2×6 = 1 BF/LF (the easy benchmark); 2×12 is 2× that; 2×4 is 2/3 of that.

Real-World Example Calculations

12 Pieces of 2×6 × 8 ft Pressure-Treated (Deck Framing)

Deck joist count for a 12×14 ft floating deck with joists 16 in OC.

T × W (nominal): 2 in × 6 in
Length per piece: 8 ft
Pieces: 12
$/BF: $2.80 (PT SYP)

BF per piece / Total BF / LF / Cost 8 BF / 96 BF / 96 LF / $269

Takeaway: Coincidence: BF/LF = 1 for 2×6, so BF = LF for this size. Receipt and plan can use either number interchangeably.

8 Pieces of 1×12 × 10 ft Cedar (Shelving)

Wall-mounted shelves for a workshop / garage; 6 shelves at 4 ft + 2 risers.

T × W (nominal): 1 in × 12 in
Length per piece: 10 ft
Pieces: 8
$/BF: $4.50 (cedar)

BF per piece / Total BF / LF / Cost 10 BF / 80 BF / 80 LF / $360

Takeaway: 1×12 is also 1 BF/LF. Cedar at $4.50/BF is the ‘decent middle’ choice for visible interior work — not as cheap as SPF, not as premium as walnut.

20 Pieces of 2×4 × 8 ft SPF (Wall Framing)

Standard 16-ft interior wall with top and bottom plates, 12 studs, kings/jacks.

T × W (nominal): 2 in × 4 in
Length per piece: 8 ft
Pieces: 20
$/BF: $1.80 (SPF #2)

BF per piece / Total BF / LF / Cost 5.33 BF / 107 BF / 160 LF / $192

Takeaway: BF (107) and LF (160) diverge sharply for 2×4 because BF/LF = 0.67. SPF framing is the cheapest residential lumber; always confirm fire-block code requirements before installing.

Sources & Standards

These references are used for terminology, safety boundaries, and engineering assumptions. Local code, supplier specifications, and licensed design documents still control your project.

American Lumber Standards Committee — Voluntary Product Standard PS 20-15 (American Softwood Lumber Standard) American Lumber Standards Committee
Referenced for nominal-vs-actual dimensional lumber sizes (2×4 actual 1-1/2 × 3-1/2, etc.) and the board-foot calculation method using nominal dimensions.
National Hardwood Lumber Association — Rules for the Measurement and Inspection of Hardwood and Cypress Lumber NHLA
Referenced for hardwood board-foot measurement and grading conventions (FAS, Select, #1 Common).
USDA Forest Service — Wood Handbook (Chapter 6: Commercial Lumber, Round Timbers, and Ties) USDA Forest Products Laboratory
Referenced for board-foot tally methods, lumber grading, and species-by-grade reference.

Frequently Asked Questions

What is a board foot?

A board foot is a volume measurement equal to 1 in × 12 in × 12 in = 144 in³. The formula: BF = (Thickness in × Width in × Length ft) ÷ 12. A 2×4 × 8 ft board is (2 × 4 × 8) ÷ 12 = 5.33 board feet.

How do I calculate board feet?

Use nominal dimensions: BF = (T_in × W_in × L_ft) ÷ 12. For multiple pieces, multiply BF per piece by the piece count. Example: 12 pieces of 2×6 × 10 ft = (2 × 6 × 10 ÷ 12) × 12 = 10 × 12 = 120 BF.

Why isn’t a 2×4 actually 2 inches by 4 inches?

Dimensional lumber is sold by nominal size (the rough-cut dimension before kiln-drying and surfacing) but delivered at actual size (after S4S planing). A nominal 2×4 is actually 1.5 in × 3.5 in. Board-foot math always uses nominal dimensions, not actual — this is industry standard per the American Lumber Standards Committee PS 20-15.

What’s the difference between board feet and linear feet?

Linear feet (LF) measures length only. Board feet (BF) measures volume. For a 2×6, BF/LF = 1 (a coincidence of the dimensions). For a 2×4, BF/LF = 0.67. For a 2×12, BF/LF = 2.0. When a plan calls for ‘100 LF of 2×12’ that’s 200 BF, not 100.

How many board feet are in a 2×4 × 8 ft?

5.33 board feet. Formula: (2 × 4 × 8) ÷ 12 = 5.33 BF. A typical bundle of 100 pieces of 2×4 × 8 ft contains 533 BF.

How much does lumber cost per board foot in 2026?

2026 Mid-Atlantic retail: SPF #2 framing $1.80/BF, Doug Fir / SYP #2 $2.20, PT SYP $2.80, Western Red Cedar $4.50, Red Oak hardwood $8.50, White Oak $10.50, Walnut $15.00. Contractor / bulk pricing typically runs 15–25% below retail.

Do I use nominal or actual dimensions for board foot math?

Always nominal. A 2×4 is 2×4 for BF purposes even though it’s actually 1.5×3.5. This is the industry standard per PS 20-15 and the way every sawmill, lumberyard, and grading agency computes BF. Using actual dimensions would under-count BF by ~25–30%.