EstimatorKitFree board foot calculator
Board feet, in quarters, priced the way a yard bills them
A board foot is 144 cubic inches of wood — one inch thick, twelve inches wide, twelve inches long — so it measures volume and never length. Enter thickness in quarters, width in inches and length however your cut list is written, line by line for a whole cart, and this returns the footage, the price at the rate per board foot you were quoted, and the same total worked out under the tally rules a hardwood yard writes an invoice with.
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- 4/4 to 16/4
- Yard tally rules
- Per-line pricing
Rough stock measures its full quarter thickness, so the two counts differ only by the yard's rounding.
4/4 is 1" rough and 13/16" surfaced — NHLA standard surfaced thickness for 4/4 rough stock. Billed at 1" either way.
4/4 is 1" rough and 13/16" surfaced — NHLA standard surfaced thickness for 4/4 rough stock. Billed at 1" either way.
8/4 is 2" rough and 1 3/4" surfaced — NHLA standard surfaced thickness for 8/4 rough stock. Billed at 2" either way.
One line per species and thickness. Prices go in per line because a cart with walnut and soft maple in it has two rates on one ticket, and leaving them blank simply drops the money column.
If the list above is finished parts rather than boards on the cart
The cabinet grade. Shorter clear pieces, and a third of the board is not one.
Board feet the ticket will say
68 bf
- Pieces
- 12
- Yard tally
- 68 bf
- Measured
- 64.5 bf
- As cubic feet
- 5.67
Where the two figures part company
The tally is 3.45 bf above what the wood measures, a gap of 5.3%. Width goes to the nearest inch, the odd inches of length are dropped.
Buying to this as a cut list at 67% yield means 101 bf of rough on the cart — 33.5 bf more than the parts, shown separately so you can hold either number against a quote.
| Line | SM | bf each | bf total |
|---|---|---|---|
| Walnut, wide stock4 × 4/4 at 9.5 in × 8.42 ft | 7 | 7 | 28 |
| Walnut, narrows6 × 4/4 at 6.25 in × 7.17 ft | 4 | 4 | 24 |
| Maple legs2 × 8/4 at 7.75 in × 6 ft | 4 | 8 | 16 |
SM is surface measure: width in inches times length in feet, divided by 12 and rounded. Multiply it by the quarter thickness and you have the tally. At 4/4 the two are the same number, which is why hardwood prices are quoted per board foot and thought about per square foot of face.
One board foot is 144 cubic inches — a board foot is a piece 1 in thick, 12 in wide and 12 in long — one twelfth of a cubic foot. Nothing on this page applies to sheet goods or to framing sold by the piece; both are counted a different way and neither is priced in this unit.
Linear feet, board feet and square feet on the same board
These three are confused constantly and they are not near-synonyms: one is a length, one is a volume and one is an area. The last three columns are the same three pieces of wood counted in every unit, so the differences are arithmetic rather than assertion.
| Unit | What it measures | What is sold in it | 1 x 6, 8 ft | 2 x 4, 8 ft | 4 x 8 sheet, 3/4 in |
|---|---|---|---|---|---|
| Linear foot | Length alone. Width and thickness are not in it. | Trim, decking, handrail, fence rail, gutter, cabinet run | 8 | 8 | Not sold this way |
| Board foot | Volume — 144 in³, on nominal or rough thickness. | Hardwood rough and surfaced, timbers, mill and freight quotes | 4 | 5.33 | 24, and no yard quotes it |
| Square foot | The face on one side only. | Plywood, OSB, flooring, siding, drywall, countertop | 4 nominal, 3.67 measured | 2.67 nominal, 2.33 measured | 32 |
| Cubic foot | Volume — 1,728 in³, twelve board feet. | Bagged material, mulch, concrete, freight volume | 0.33 | 0.44 | 2 |
Read the 1 x 6 column across and the whole confusion resolves: the same eight-foot board is 8 linear feet, 4 board feet and 4 square feet of face, and only one of those three numbers is what a hardwood dealer will charge you for. When the material is bought by the running foot instead, the count and the offcuts are on the linear feet calculator.
How to work out board feet for a hardwood order
Thickness in quarters, a line per board, then the gap between the tape and the ticket.
Set the thickness in quarters, not in inches
Hardwood thickness is quoted as quarters of an inch of rough stock: 4/4 is an inch, 5/4 is an inch and a quarter, 8/4 is two inches. Pick the quarter size the price list uses, and say whether the boards in front of you are rough or surfaced. The choice changes what a tape will find on the board and changes nothing at all about what you are charged, which is the single most common surprise on a first hardwood order.
Put every board on the cart into its own line
Hardwood comes in random widths and lengths, so a cart is a list rather than a quantity. Each line takes a piece count, a width in inches and a length — 8 ft 5 in, 101 in and 2.57 m all read the same. Give each line the price per board foot for that species and thickness, because walnut and soft maple on one ticket are two rates, and lines left blank simply drop out of the money column.
Compare the tally against the tape, then allow for the cut list
The panel gives the footage the ticket will carry and the footage the wood actually measures, with the gap between them worked out as a percentage. Under it, if the list you typed is finished parts rather than boards, choose the grade and the page turns the net footage into rough board feet to buy at that grade's own guaranteed yield — 83 1/3% for FAS, 66 2/3% for No. 1 Common.
Technical specifications
| Board foot | 144 cubic inches — a block 1 in thick and 12 in square, so the unit is a volume and cannot be a length |
|---|---|
| Quarter sizes | 4/4, 5/4, 6/4, 8/4, 10/4, 12/4 and 16/4 rough — 1 in to 4 in in quarter-inch steps |
| Surfaced thicknesses | 13/16, 1 1/16, 1 5/16, 1 3/4, 2 1/4, 2 3/4 and 3 3/4 in for those seven, per the NHLA standard |
| Tally rounding | Width to the nearest inch, length with odd inches dropped, surface measure rounded again |
| Grade yields | FAS 83 1/3%, No. 1 Common 66 2/3%, No. 2A Common 50% clear cuttings — editable, and the default for the buy figure |
| List length | Up to 24 lines, each with its own quarter size, piece count and price per board foot |
| Softwood note | A 2 x 4 x 8 ft tallies 5.33 bf on nominal size against 3.5 bf of wood you can measure |
| Leaves the browser | Nothing — the quarter ladder and the grade yields compile into the page, so the tally still runs at a sawmill with no bars |
Frequently asked questions
What does 4/4 mean on a hardwood price list?
It is the rough thickness of the board in quarters of an inch, so 4/4 is one inch, 5/4 is an inch and a quarter and 8/4 is two. The trade says it out loud as four-quarter and eight-quarter, never as one inch and two inch, and the ladder runs 4/4, 5/4, 6/4, 8/4, 10/4, 12/4 and 16/4. It describes the log at the moment it was cut, before drying and before any surfacing, which is why it survives as the billing thickness even on a board that has since lost 3/16 of an inch on a planer.
Why is my surfaced 4/4 board 13/16 inch thick and still billed as 4/4?
Because you are paying for the wood the mill cut, not the wood left after it was flattened. The NHLA standard surfaced thickness for 4/4 stock is 13/16 in, for 5/4 it is 1 1/16, for 6/4 it is 1 5/16 and for 8/4 it is 1 3/4 — everything up to 6/4 loses 3/16 on the planer and everything from 8/4 up loses a quarter. That shaving is not a discount available to you: it was sawn, dried and handled as full thickness, and the surfacing is a service the yard adds on top. The practical consequence is a design one. If a drawing calls for a finished 3/4 in part, 4/4 gets there with 1/16 to spare and no more, so a board with any cup in it will not make the thickness.
Why is the yard's tally higher than the board feet I worked out?
Three roundings, all of them in the seller's favor and all of them published. Width is measured to the nearest inch with a half inch counting as a full one, so a 6 3/4 in board tallies as 7. Length is measured in whole feet with the odd inches dropped, so an 8 ft 5 in board tallies as 8. Those two make surface measure, which is rounded again to a whole number before it is multiplied by the quarter thickness. On a cart of clean wide stock the gap is a percent or two; on a pile of narrow shorts it is visible enough to argue about, which is why this page prints both figures rather than one.
Is plywood sold in board feet?
No, and neither is anything else that comes as a sheet. Plywood, OSB, MDF and particleboard are sold by the sheet and estimated in square feet, because their thickness is fixed by the product rather than chosen by the buyer. A 4 by 8 sheet of 3/4 in plywood does contain 24 board feet of wood by volume, and quoting it that way would be as useful as pricing a window by the pound. Sheets belong on the plywood calculator, which counts them whole and reports what a 4 by 8 leaves over on an odd-sized room.
Do 2x4s have a board footage?
They do, and it is calculated on the nominal size, which is the one trap in the whole unit. A 2 by 4 by 8 ft is 5.33 board feet — two times four times eight, over twelve — even though the piece measures 1.5 by 3.5 and holds only 3.5 board feet of actual wood. Mills, wholesalers and freight quotes all run on the nominal figure, so a thousand board feet of 2 by 4 is a defined quantity of sticks. At a retail counter none of this is visible: framing lumber is sold by the piece at a price per stick, which is why a framing take-off counts pieces rather than footage.
How much rough lumber do I buy for a cut list that needs 40 board feet?
Start from the grade's own yield and expect to do slightly worse. The NHLA grades are defined by the share of the board that comes out as clear cuttings: FAS guarantees 83 1/3%, No. 1 Common 66 2/3%, No. 2A Common 50%. So 40 net board feet is 48 rough in FAS and 60 in No. 1 Common — and those are floors, not forecasts, because your parts have specific lengths and widths that the grade rule knows nothing about. Long wide parts do worse than the rule; short narrow ones do better. Matching color across a panel does worse than either.
Can I ask for six boards 6 inches wide and 8 feet long?
Not at a hardwood yard, no. Hardwood is sold random width and random length: the tree decides, the grader sorts by how much clear wood is in each board, and what reaches the rack is a pile of 5 to 12 in widths in 6 to 16 ft lengths. You order board feet of a species, thickness and grade, then pull boards until the tally is met. This is why a cut list has to be turned into footage before anyone can quote it, and why two carts of the same footage can yield very different parts — a fact no calculator can fix and every hardwood buyer works around by choosing boards rather than accepting them.
About the board foot, the quarter system and the hardwood tally
The board foot survives because it prices a log rather than a product. A sawyer cutting a walnut butt does not know whether it will become a table top or a drawer side, so the trade settled on a unit of volume — 144 cubic inches, one twelfth of a cubic foot — and quoted thickness in quarters of an inch of rough stock: 4/4, 5/4, 6/4, 8/4 and up. Every part of that is about the wood as it left the saw. It is why a surfaced board still carries the quarter size it was cut at, why the ladder is written in quarters rather than decimals, and why the unit stops being useful the moment a manufacturer fixes the thickness for you. Sheet goods have their thickness chosen at the factory and are counted by the sheet on the plywood calculator; framing lumber has its section fixed by the grade stamp and is counted by the piece on the framing calculator. Neither is bought in this unit, whatever a volume conversion says.
The tally is where a first hardwood invoice goes sideways. Under the NHLA rules a board is measured for width to the nearest inch — a half inch and over counting as a full one — and for length in whole feet with the odd inches dropped. Those two make surface measure, which is width in inches times length in feet over twelve, rounded to a whole number, and board feet are surface measure times the quarter thickness. At 4/4 those two numbers are identical, which is why hardwood is priced per board foot and thought about per square foot of face. None of this is sharp practice; it is published, it is how every yard in the country writes a ticket, and the reason to reproduce it here is that a customer who multiplies three exact measurements will always come out a little under the invoice and wonder why. Grade works the same way: FAS, No. 1 Common and No. 2A Common are defined by the minimum share of the board that comes out as clear cuttings, 83 1/3%, 66 2/3% and 50%, which is exactly the number to start a cut-list allowance from.
What a board foot cannot tell you is whether the boards will make your parts. Hardwood arrives random width and random length, so 60 board feet of 4/4 cherry might be four wide boards or eleven narrow ones, and a 30 in wide panel needs a particular set of widths rather than a footage. That is the argument for pulling boards yourself and for buying by the part rather than the pile wherever the parts are large. Once the stock is home the other units take over: pieces cut to a single length each need their own board, which is the arithmetic behind a rafter cut list and behind the roofing calculator above the framing, while anything bought by the running foot is counted a different way again.
What happens to your cut list
Every number on this page is worked out by JavaScript running in the tab you are reading it in. Nothing you type — measurements, quantities, the prices your supplier quoted you — is uploaded, logged or kept, which is also why the calculators carry on working on a site with no signal.
The species, the footage and the rate your yard quoted stay in the tab. No lumber dealer is told what you are pricing, and the tally is not saved between visits — closing the page loses the list, which is what the copy button is for.