Firewood Calculator
Cords, weight and the heat moisture costs you.
Work out Firewood. Cords, weight and the heat moisture costs you. Refuses out-of-range input instead of guessing.
Usually the log length.
Oak 700, ash 650, birch 600, pine 450, all when dry.
Seasoned wood is under 20%. Freshly cut can be over 50%.
Stacked volume
0.795 cords
2.88 m³ · about 1,188 kg
A stack is not solid wood. Air gaps between split logs are typically about 25% of the stacked volume, which is why firewood is sold by stacked measure and why two stacks of the same size can differ noticeably in weight. Moisture is the figure that matters most for heat. Water carries no energy and takes energy to boil off, so wet wood loses twice over — at 50% moisture the usable heat is roughly half that of seasoned wood, and the rest goes up the chimney as steam. A cord is a precisely defined 128 cubic feet stacked, or 3.62 m³. A face cord or rick is not defined at all and depends entirely on log length, which is where most firewood disputes start.
How the Firewood Calculator works
Enter stack dimensions for the volume in cords and cubic metres, the approximate weight and the usable heat. Moisture is the figure that matters most — wet wood loses roughly half its heat to boiling off water.
Also known as: how many cords in a stack · cord of wood calculator · face cord vs full cord · firewood btu calculator
Frequently asked questions
How big is a cord of wood?
128 cubic feet stacked, or 3.62 m³ — commonly a stack 8 feet long, 4 feet high and 4 feet deep. It is a precisely defined measure, unlike most firewood terms.
What is a face cord?
Not a defined unit at all. It is a stack 8 feet by 4 feet with a depth of whatever the logs happen to be, so a face cord of 16-inch logs is a third of a real cord. Most firewood disputes start here.
How much does moisture matter?
Enormously. Water carries no energy and takes energy to evaporate, so wet wood loses twice over. At 50% moisture the usable heat is roughly half that of seasoned wood, and the difference goes up the chimney as steam.
How long does firewood take to season?
Typically six to twelve months split and stacked under cover with airflow, longer for dense hardwoods. Unsplit rounds season very slowly because bark holds moisture in.
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