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Firewood Calculator: Cords, Face Cords and How Much You Need
Measure a woodpile and convert it to full cords and face cords, see what you are really paying per cord, or estimate how much firewood it takes to get through the winter.
Cord, face cord, rick: what you're actually buying
A full cord is the legal unit in most states: wood stacked tightly, 4 feet high, 8 feet long and 4 feet deep, for 128 cubic feet. Because of air gaps, only about 80 to 90 cubic feet of that is wood.
A face cord is a stack 4 feet high and 8 feet long but only one log deep. Its size depends entirely on the log length. Many sellers also call this a rick, a stove cord or a run, and the words mean different things in different regions. That's why the only safe way to compare offers is by volume.
| Log length | One face cord / rick | Face cords per full cord |
|---|---|---|
| 12 in | 1/4 cord (32 cu ft) | 4 |
| 16 in (most common) | 1/3 cord (42.7 cu ft) | 3 |
| 18 in | 3/8 cord (48 cu ft) | 2.67 |
| 24 in | 1/2 cord (64 cu ft) | 2 |
So a $150 face cord of 16 inch logs is really $450 per full cord. Thrown (unstacked) loads in a truck bed take up more room than stacked wood, so measure after stacking.
How much firewood do I need?
Firewood needs are easiest to estimate from the fuel you burn now. The calculator works out how much heat your house actually used, then how many cords deliver the same heat in your stove:
Example: a home burning 500 gallons of oil a year in an 80% boiler uses about 55 million Btu of heat. If a wood stove takes half of that load with red oak (24.6 million Btu per cord) in an EPA-certified stove (68%), you need about 1.7 cords. Heating entirely with wood would take about 3.3 cords of oak, or about 5 cords of pine.
The heat values per cord come from Utah State University Extension's firewood table and assume dry, seasoned wood. Freshly cut wood can be 40% water or more, and boiling that water off wastes a big share of the heat while coating the chimney with creosote. Wood should dry to about 20% moisture, usually 6 to 12 months split and stacked under cover, longer for oak. A cheap moisture meter on a freshly split face settles the question.
The stove efficiencies are EPA's figures: about 68% for certified stoves and 54% for older uncertified ones. EPA says a certified stove can use up to a third less wood for the same heat. An open fireplace is far less efficient and isn't a practical primary heat source.
Tips before you buy
Ask for the stack dimensions and log length, not just "a cord" or "a rick". Ask whether the wood is seasoned and how long it has been split. Buy local wood: moving firewood spreads invasive insects such as the emerald ash borer, and many states restrict it. Stack off the ground, bark side up, with the ends open to the wind, and keep at least a week's supply indoors or under cover so it's dry when you need it.
Frequently asked questions
What is the difference between a cord and a face cord?
A full cord is a tightly stacked pile 4 feet high, 8 feet long and 4 feet deep, 128 cubic feet. A face cord (often called a rick) is also 4 by 8 feet but only one row of logs deep. With 16 inch logs, a face cord is one third of a full cord.
How much is a rick of wood?
A rick usually means the same thing as a face cord: a 4 by 8 foot stack, one log deep. Its volume depends on log length, so with 16 inch logs it's 1/3 cord, with 12 inch logs 1/4 cord and with 24 inch logs 1/2 cord. Ask the seller for the log length and the stack dimensions.
How many cords of wood do I need for a winter?
If wood is your main heat in a cold climate, often 3 to 6 cords. As a supplement on evenings and weekends, 1 to 2. Replacing 500 gallons of heating oil takes about 3.3 cords of red oak in an EPA-certified stove.
How much does a cord of firewood weigh?
A lot. According to Utah State University Extension, a cord of dry red oak weighs about 3,500 lb and dry white oak about 4,200 lb, while softwoods such as white pine are closer to 2,200 lb. Green wood is heavier still. A half-ton pickup holds well under a cord by weight.
Which firewood gives the most heat?
Dense hardwoods. Per cord, white oak (about 29 million Btu), black locust (28), beech (27.5) and sugar maple (25.5) lead the common species. Pine, spruce and cottonwood give about 15 to 16 million Btu. All wood has about the same heat per pound; dense wood simply packs more pounds into a cord.
Sources
- Utah State University Extension, Wood Heating, Table 1: Firewood facts: heat per cord (million Btu) and dry weight per cord by species.
- U.S. EPA, AP-42 section 1.10, Residential wood stoves: net efficiency of conventional (54%) and certified (68%) stoves; Burnwise FAQ: certified stoves use up to one-third less wood.
- EIA, Energy units: 20 million Btu per cord generic value, plus oil, propane, natural gas and electricity conversions.
- Cord definition (4 × 4 × 8 ft, 128 cu ft): NIST Handbook 130, uniform method of sale for fireplace and stove wood, adopted by most states.
Last reviewed October 25, 2026. Estimates only; see the disclaimer.