What Is a Cord of Wood? How to Measure Firewood

What a cord is

The definition many US states work from is in NIST Handbook 130, the collection of model weights and measures laws and regulations that states adopt. Section 2.4.1.2 reads:

Two things follow from that wording. First, a cord is a volume of stacked wood, not a weight and not a pile. Second, the shape does not matter, only the volume does. The usual picture is a stack 4 feet high, 4 feet deep and 8 feet long: 4 × 4 × 8 = 128 cubic feet. The firewood tip sheet from the National Conference on Weights and Measures, hosted by NIST, shows a second shape that is just as legal: 2 feet deep, 4 feet high and 16 feet long, also 128 cubic feet.

Because the definition counts the space the stacked wood fills, the gaps between round and split pieces are part of a cord. That is why stacking matters so much: a loose heap cannot be measured against the definition at all, and the NCWM tip sheet tells buyers to stack the wood compactly, with as few gaps as possible, before measuring.

Face cord, rick, rack and truckload

Handbook 130 is blunt about the other words used for firewood. Section 2.4.3 says fireplace and stove wood shall be sold only by measure, “using the term ‘cord’ and fractional parts of a cord or the cubic meter”, with exceptions for small packaged wood, pressed logs and pellets. Section 2.4.4 then says:

The NCWM tip sheet gives the reason: these terms “have no legally defined meaning”, so a buyer has no way of telling how much wood they are getting. The Washington State Department of Agriculture says the same on its firewood page, and the Connecticut Department of Consumer Protection publishes the handbook wording as its firewood regulation.

The word “rick” does not appear in Handbook 130. Whether a state treats it as a “term of similar import” is a question for that state. This matters because the handbook is a model, not a federal law. Its own abstract says the model regulations are adopted “in various forms” by many state and local authorities: some adopt the current version, some an older one, some use it only as a guideline and some have their own rules. If you want to know exactly what applies where you live, ask your state weights and measures office. In Washington it is part of the Department of Agriculture, in Connecticut part of the Department of Consumer Protection.

None of this means a seller who says “face cord” is cheating you. It means the phrase does not tell you a volume, so you have to turn it into one yourself. That is what the next two sections do.

What a “face cord” holds at each piece length

When a seller describes a face cord as one row 4 feet high and 8 feet long, the volume depends entirely on how long the pieces are, because piece length is the depth of the row. The table works it out for a range of lengths. The formula is 4 × 8 × piece length in feet, divided by 128.

Two rows stand out. A row of 16-inch pieces is exactly one third of a cord, 42.7 cubic feet, and three such rows side by side make a full cord. A row of 48-inch pieces, four feet deep, is the whole cord on its own: that is the 4 × 4 × 8 stack. Shorter pieces, which suit small stoves, give less wood per row, so a price “per face cord” for 12-inch wood buys a quarter of a cord, not a third.

Fractions of a cord

Sellers who follow the handbook quote cords and fractions of a cord. The table turns each fraction into cubic feet and cubic meters, and shows how long a single row of 16-inch pieces, stacked 4 feet high, has to be to hold it.

The first row has a second meaning. Handbook 130 treats wood packaged in quantities under 1/8 cord, 16 cubic feet or 0.45 m³, differently: it must show its quantity on the package in liters, and may add cubic feet. Small packaged bundles fall under this rule. More on comparing them below.

How to measure a stack you bought

The NCWM tip sheet says to measure the wood before using any. Stack it first, or ask the seller to stack it, since you may pay extra for that. Then:

1. Stack tight, parallel rows. Pieces touching and parallel, as few gaps as possible. Crossed or tumbled pieces add air, not wood.
2. Measure each row's length along the ground, in feet.
3. Measure the height at three or more points along the row and take the average. Tops are rarely flat.
4. Measure the piece length of several pieces from the row and take the average. This is the depth of the row.
5. Multiply and divide. Length × average height × average piece length gives cubic feet for the row. Add the rows and divide by 128.

Dividing by 12 turns piece length from inches into feet; dividing by 128 turns cubic feet into cords. The volume calculator does the length × height × depth step for a box shape if you prefer to type the numbers in, and gives the answer in several units at once.

Example 1: half a cord in one row

You ordered half a cord of 16-inch wood and stacked it in one row 12 feet long and 4 feet high. The volume is 12 × 4 × 16 ÷ 12 = 64.0 cubic feet, and 64.0 ÷ 128 = 0.50 cord. That is exactly what you paid for. The fractions table above gives the same answer: half a cord of 16-inch wood is a 4-foot-high row 12.0 feet long.

Example 2: a full cord in three rows

You ordered one cord. Five pieces you measure are 15.5, 16, 16.5, 15, 16 inches long, an average of 15.8 inches. You stack the wood in three rows, each 8 feet long, and measure each row's height at three points.

The stack holds 120.8 cubic feet, which is 0.944 cord: 7.2 cubic feet, or 5.6 percent, short of what you paid for. Most of the gap is the low third row. Before you call the seller, re-check the stacking: a loose row with big gaps can sometimes be restacked tighter, but restacking never adds wood, it only removes air you would otherwise be counting.

Example 3: a stack measured in meters

If your tape is metric, the same method gives cubic meters. A row 3 m long and 1.2 m high of pieces 40 cm long is 3 × 1.2 × 0.4 = 1.44 m³. Dividing by 3.625 gives 0.397 cord.

The delivery ticket and what to do if you are short

Under Handbook 130, section 2.4.5, a seller of non-packaged firewood must give the buyer a delivery ticket or sales invoice with at least:

• the name and address of the vendor;
• the name and address of the purchaser;
• the date delivered;
• the quantity delivered, and the quantity the price is based on if that differs;
• the price of the amount delivered; and
• the identity of the wood in the most descriptive terms practicable, including any quality claim made in the sale.

Section 2.4.2 adds that if a seller states the species, for example half hickory and half mixed softwood, the percentages must be accurate within 10 percent.

The NCWM tip sheet adds practical steps. If you can, write down the seller's phone number and the license plate of the delivery vehicle. If your measurement shows less than you paid for, contact the seller before you burn any wood. If the seller cannot or will not fix it, contact your state weights and measures authority, again before burning, and take a photo of the stacked wood to document the shortage. Burning the wood first destroys the evidence.

Cubic meters and steres

Handbook 130 allows firewood to be sold by the cubic meter as well as by the cord. Since the foot is exactly 0.3048 meters, a cubic foot is 0.028317 m³ and a cord is 3.6246 m³; NIST's SI guide (SP 811) lists the cord as 3.624 556 m³. The same guide lists the stere as exactly one cubic meter.

The handbook defines the cord as stacked wood, ranked and well stowed, and does not set out a separate loose measure. If a seller quotes cubic meters, ask whether that means stacked, and measure the stack the same way as above. For other volume units, the volume converter handles cubic feet, liters and gallons.

Comparing prices across units

Offers in cords, fractions, cubic meters and bundles only compare once they are in the same unit. Divide each price by the amount in cords to get a price per cord. The prices below are made-up examples to show the arithmetic, not market prices.

A bundle labeled 0.75 ft³ is 0.0059 cord, so it takes 170.7 such bundles to make a cord. Bundles are convenient for a single evening, but run the division before buying them in any quantity. If the label shows only liters, divide by 28.32 to get cubic feet first.

Is the wood ready to burn?

Volume is only half of what you are buying. EPA's Burn Wise pages give this guidance on seasoned wood. EPA notes that it stopped updating the program's content on October 30, 2025 and keeps the site as a historic record.

• Wood burns best at a moisture content of less than 20 percent. Check it with a wood moisture meter before burning.
• Season wood for at least six months.
• Seasoned wood is darker, lighter in weight, and sounds hollow when struck against another piece of wood.
• Store wood outdoors, off the ground, with only the top covered; covering the sides traps in moisture.

The same page lists things not to burn, among them coated, painted and pressure-treated wood, plywood, particle board or any wood with glue on or in it, and wet, rotted, diseased or moldy wood. If a seller describes wood as seasoned, that description belongs on the delivery ticket under section 2.4.5(f), as a quality representation made in the sale.

Buy it where you burn it

The US Department of Agriculture's Animal and Plant Health Inspection Service asks people to buy firewood where they burn it, calling it the easiest way to reduce the spread of invasive pests. It notes that even short-distance travel can spread pests unless firewood has been properly treated, and to use heat-treated firewood if you must move it.

Buying checklist

• Ask for the amount in cords or fractions of a cord, or in cubic meters. Turn any “face cord”, “rick” or “truckload” into cubic feet before agreeing a price.
• Ask the piece length. It decides how much wood a 4 × 8 ft row holds.
• Compare by price per cord, not price per offer.
• Get the delivery ticket with the items section 2.4.5 lists.
• Stack and measure before burning. Length × average height × average piece length ÷ 12 ÷ 128.
• Check moisture with a meter if the wood is sold as ready to burn.
• Buy local. Don't carry firewood long distances.

Mulch, gravel, soil and concrete are a different measuring job: they are ordered by the cubic yard, which cubic yards explained covers with coverage and bag tables.

Frequently asked questions

Sources

• NIST Handbook 130 (2026), Uniform Regulation for the Method of Sale of Commodities, section 2.4 Fireplace and Stove Wood (pp. 116–117) and Abstract
• NCWM tip sheet hosted by NIST: Avoid Getting Burned When Buying Firewood
• Washington State Department of Agriculture: Firewood (weights and measures)
• Connecticut Department of Consumer Protection: Firewood and Stove Wood Regulations
• NIST SP 811, Appendix B.8: Factors for units listed alphabetically (cord, cubic foot, stere)
• EPA Burn Wise: Best Wood-Burning Practices
• USDA APHIS: Only Buy Firewood Where You Burn It

Written by Tobias. Updated October 22, 2026.