Free Online Calculators
Cord/stere/loose ↔ conversions + heat value by wood type
Firewood is sold in several different units depending on where you live. In North America, the standard unit is a cord of wood — a neatly stacked pile measuring 4 × 4 × 8 feet, equal to 128 cubic feet or roughly 3.62 cubic meters. In Europe, the stere (1 cubic meter of stacked wood) is the common unit. Converting between these measurements used to require manual math, but a firewood calculator makes it instant and accurate.
Why does the unit matter? Because firewood is priced and sold by volume, but what you actually pay for is heat output. Two cords of wood can deliver wildly different amounts of energy depending on species and moisture content. A cord of dry oak produces roughly 26–29 million BTU, while a cord of pine delivers closer to 17–18 million BTU. Knowing the difference helps you buy smarter and budget your heating season properly.
Hardwoods are denser and store more energy per cubic meter than softwoods. Oak and beech are top-tier choices for heating — beech averages around 2,100 kWh per stere, and oak comes in just behind at roughly 2,050 kWh per stere. These are excellent for long, steady burns through cold nights. Birch is a popular middle-ground option, offering about 1,900 kWh per stere with a pleasant smell and good flame.
Softwoods like pine and spruce burn faster and produce less heat per unit — typically 1,400–1,600 kWh per stere. They're not bad choices for shoulder-season heating or getting a fire started quickly, but for an all-winter primary heat source, you'll need significantly more volume. The heating oil equivalent comparison puts this in perspective: 1 stere of dry beech replaces roughly 160–170 liters of heating oil, while a stere of spruce replaces only about 110 liters.
All these values assume properly seasoned or kiln-dried wood with a moisture content below 20%. Wet or green firewood can lose 30–50% of its effective heating value because energy goes into evaporating water rather than producing heat. Always verify moisture content before buying in bulk.
This tool on simple-calculator.online lets you enter a quantity in cords, steres, or cubic meters and instantly see the converted volumes alongside the estimated heating output in both kWh and BTU for five common wood species. For example, if you have 2 steres of oak, you can immediately see that equals roughly 0.55 cords and delivers approximately 4,100 kWh — enough to heat a well-insulated room for several months.
Use the heating oil equivalent feature to compare firewood costs against your current fuel. If oil costs €1.10 per liter and a stere of beech replaces 165 liters, that stere delivers the equivalent of €181 in oil value. If you can buy seasoned beech for less than that, firewood is the better deal financially.
One full cord equals approximately 3.62 cubic meters of stacked wood. However, since a cord includes air gaps between logs, the actual solid wood content is closer to 2.4–2.5 cubic meters.
Oak and beech consistently rank highest among common firewood species. Dry oak delivers roughly 26–29 million BTU per cord, making it one of the most energy-dense and cost-effective heating woods available.
Yes, significantly. Freshly cut (green) wood can have 50% moisture content, which cuts effective heat output nearly in half. Always use wood seasoned for at least 12–18 months, or kiln-dried wood tested below 20% moisture.