How much heat is in a cord of firewood? Almost all of the difference between woods comes from density: a pound of dry wood holds about the same heat whatever the species, so a cord of dense hickory or oak holds nearly twice the heat of a cord of light aspen or white pine. This chart works out the heat in a full cord for 29 common North American firewoods from their USDA Wood Handbook densities and the US Forest Service’s fuel value of wood, along with what each cord weighs freshly cut and seasoned.
Firewood BTU and weight per cord
| Wood | Type | Basic specific gravity | Heat per cord (million Btu, gross) | Usable heat, seasoned, 77% (million Btu) | Cord weight, seasoned (lb) | Cord weight, green (lb) |
|---|---|---|---|---|---|---|
| Black locust | hardwood | 0.66 | 28.3 | 21.8 | 4,120 | — |
| Hickory (shagbark) | hardwood | 0.64 | 27.5 | 21.2 | 3,996 | 5,146 |
| White oak | hardwood | 0.60 | 25.8 | 19.8 | 3,746 | 5,124 |
| Red oak (northern) | hardwood | 0.56 | 24.1 | 18.5 | 3,496 | 4,881 |
| Sugar (hard) maple | hardwood | 0.56 | 24.1 | 18.5 | 3,496 | 4,713 |
| American beech | hardwood | 0.56 | 24.1 | 18.5 | 3,496 | 4,573 |
| White ash | hardwood | 0.55 | 23.6 | 18.2 | 3,434 | 3,983 |
| Yellow birch | hardwood | 0.55 | 23.6 | 18.2 | 3,434 | 4,752 |
| Black walnut | hardwood | 0.51 | 21.9 | 16.9 | 3,184 | 4,623 |
| Hackberry | hardwood | 0.49 | 21.0 | 16.2 | 3,059 | 3,989 |
| Red (soft) maple | hardwood | 0.49 | 21.0 | 16.2 | 3,059 | 4,160 |
| Paper birch | hardwood | 0.48 | 20.6 | 15.9 | 2,997 | 4,327 |
| Black cherry | hardwood | 0.47 | 20.2 | 15.5 | 2,934 | 3,873 |
| Southern pine (loblolly) | softwood | 0.47 | 20.2 | 15.5 | 2,934 | 4,026 |
| American elm | hardwood | 0.46 | 19.8 | 15.2 | 2,872 | 4,446 |
| American sycamore | hardwood | 0.46 | 19.8 | 15.2 | 2,872 | 5,100 |
| Sweetgum | hardwood | 0.46 | 19.8 | 15.2 | 2,872 | 4,779 |
| Douglas-fir | softwood | 0.45 | 19.3 | 14.9 | 2,809 | 3,259 |
| Silver maple | hardwood | 0.44 | 18.9 | 14.6 | 2,747 | 3,901 |
| Yellow-poplar (tulip poplar) | hardwood | 0.40 | 17.2 | 13.2 | 2,497 | 3,886 |
| Ponderosa pine | softwood | 0.38 | 16.3 | 12.6 | 2,372 | 3,682 |
| Lodgepole pine | softwood | 0.38 | 16.3 | 12.6 | 2,372 | 3,426 |
| Eastern hemlock | softwood | 0.38 | 16.3 | 12.6 | 2,372 | 3,948 |
| Eastern cottonwood | hardwood | 0.37 | 15.9 | 12.2 | 2,310 | 4,666 |
| Quaking aspen | hardwood | 0.35 | 15.0 | 11.6 | 2,185 | 3,566 |
| Eastern white pine | softwood | 0.34 | 14.6 | 11.2 | 2,123 | 3,226 |
| White spruce | softwood | 0.33 | 14.2 | 10.9 | 2,060 | 2,555 |
| Basswood | hardwood | 0.32 | 13.7 | 10.6 | 1,998 | 3,308 |
| Western redcedar | softwood | 0.31 | 13.3 | 10.3 | 1,935 | 2,508 |
How the numbers are worked out
- Heat per pound is nearly constant. The Forest Products Laboratory uses 17.2 million Btu per ton of ovendry wood, 8,600 Btu per pound, for both hardwoods and softwoods.
- So heat per cord follows density. The Handbook’s basic specific gravity is ovendry weight divided by green volume, which is the right measure for wood that was split and stacked green and shrank a little as it dried.
- How much wood is in a cord? A cord is 128 cubic feet of stacked wood (4 × 4 × 8 ft), but much of that is air. We assume 80 cubic feet of solid wood; small, crooked or loosely stacked pieces hold less, straight tight splits more, so treat every figure as ±10% or so.
- A cross-check. The Forest Service’s own fuel comparison uses 20 million Btu gross per cord of seasoned firewood. At 80 cubic feet that corresponds to wood with a basic specific gravity of about 0.47, about the density of black cherry or southern pine, which fits a typical cord of mixed woods.
Seasoned vs green: why dry wood matters
Freshly cut wood is heavy with water: a cord of green red oak weighs about 4,881 lb against 3,496 lb seasoned, according to the table. All that water has to be boiled off in the stove, and the Forest Service figures show the cost: it uses an efficiency of 67% for green wood at 50% moisture and 77% for air-dried wood at 20%. Burning green wood also makes more smoke and creosote. Split wood, stack it off the ground with the top covered and the sides open, and give it a summer or more to dry; dense woods such as oak take longest. See how long to dry lumber for the Forest Service drying times of boards, which dry faster than rounds and splits.
What the chart means for choosing firewood
- Best heat per cord: hickory, black locust, white and red oak, hard maple, beech and white ash. They also burn longest per load.
- Good all-round: yellow and paper birch, black cherry, red maple, hackberry and elm (hard to split when twisted grain is present).
- Light woods: aspen, cottonwood, basswood, white pine, spruce and cedar have roughly 55 to 65% of the heat of oak per cord. Fine for kindling, shoulder-season fires and quick heat.
- Softwoods are not dangerous if seasoned; creosote comes from wet wood and smouldering fires more than from species.
- Pricing: compare price per million Btu, not per cord. At equal price per cord, red oak gives about 1.6 times the heat of eastern white pine.
Frequently asked questions
What firewood has the highest BTU?
Among common North American woods, hickory and black locust, then white oak, red oak, hard maple and beech. A seasoned cord of shagbark hickory holds about 27 million Btu by our estimate, against about 15 million for aspen.
How much does a cord of oak weigh?
About 3,496 lb seasoned and 4,881 lb green for northern red oak, and about 3,746 lb seasoned and 5,124 lb green for white oak, assuming 80 cubic feet of solid wood in the cord.
How many BTUs are in a cord of wood?
The US Forest Service uses 20 million Btu gross for a cord of seasoned firewood, about 15.4 million Btu of usable heat at 77% efficiency. Dense hardwoods hold more, light softwoods less; see the chart.
Is pine bad firewood?
Not if it is seasoned. Pine has about half to two-thirds the heat of oak per cord and burns faster, but creosote comes mainly from wet wood and smouldering fires.
What is a face cord?
A face cord (or rick) is one stack 4 ft high and 8 ft long but only as deep as one piece, usually 16 in, so about a third of a full cord. Ask the seller the piece length.
Sources
- USDA Forest Service, Forest Products Laboratory. Techline: Fuel Value Calculator (updated January 2024): heating values of ovendried and air-dried wood, seasoned firewood per cord, and efficiencies. A US Government work.
- USDA Forest Products Laboratory, Wood Handbook FPL-GTR-190 (2010): basic specific gravity (Tables 5-3, 5-4).
- Forest Products Laboratory. 1999. Air Drying of Lumber. FPL-GTR-117, Table 1 (average moisture content of green wood).
- NIST Handbook 130, Uniform Laws and Regulations (method of sale of commodities): a cord is 128 cubic feet of wood when ranked and well stowed.
Last reviewed: 25 October 2026. Related: wood species database, lumber weight chart, wood weight calculator. Spotted an error? Please let us know.