Firewood BTU Calculator

A bargain softwood cord is rarely a bargain. White pine at 15.9 MMBTU delivers barely 60% of hickory's heat per cord.^[1] Compare delivered price against MMBTU, not against the stack, or you'll pay more to stay warm.

Green oak needs one to two years to season.^[1] Buy it green in fall and it hisses, smokes, and wastes its heat.^[4] Buy oak already seasoned, or stack it a full year ahead.

A cord is a fixed stack of 128 cubic feet, but the heat inside it swings almost twofold depending on species. MMBTU per cord is the million BTU of stored energy in that stack: hickory holds 27.7 and white oak 26.3, while white pine holds just 15.9.^[1] Two cords of pine roughly equal one cord of hickory for actual heat delivered, so the real question is never how many cords you have; it is how many MMBTU you stacked. Buy on energy content and a pricier dense hardwood usually wins on heat delivered.

All energy figures are EIA cordwood values.^[1]

Lower BTU does not mean useless. Lodgepole pine holds 21.1 MMBTU per cord, more than birch or ash, and splits far easier while catching fast.^[1] Ash's real edge is that it burns even when barely seasoned, so it saves you when you are caught short. White pine at 15.9 is the exception: reserve it for kindling and quick spring fires, never overnight loads. In much of the West, softwood is what is cheap and local, and a fast-lighting shoulder-season fire does not need oak-grade density.

To compare value, divide each species' delivered price by its MMBTU per cord, not by the stack. If a cord of dense oak at 26.3 MMBTU costs the same as a cord of pine at 15.9, the oak delivers about 65% more heat for the identical outlay.^[1] The trap is a cheap softwood cord that looks like a deal until you realize you will burn through two of them to match one hardwood cord. Run your local delivered prices against these BTU figures before buying; paying more per cord for a dense hardwood is often the cheapest heat on the lot.

None of these figures reach your room intact. An EPA-certified stove runs 63% to 83% efficient, so a cord of white oak's 26.3 MMBTU actually delivers roughly 16.6 to 21.8 MMBTU as usable heat.^[4] That efficiency gap is wider than the difference between many species, so an old smoke-dragon stove wastes more heat than upgrading from maple to hickory would ever recover. Fix the stove before you fuss over the last MMBTU of species choice, and burn only well-seasoned wood; wet wood tanks efficiency and drives the smoke EPA warns about.^[4]

Match species to burn duration. Hickory at 27.7 and white oak at 26.3 MMBTU per cord pack the most energy into each log, so they coal down slowly and hold overnight without a reload.^[1] Save your hickory and oak for the last load before bed and the workday hours you are away; burn faster, lower-density species like birch or maple during the day when you are around to feed the stove.

Dense hardwoods carry more water and dry slower: red oak and white oak need a full one to two years split and stacked before they hit good burning moisture, while ash and softwoods are ready in months.^[1] Buying oak green in fall to burn that same winter is the most common firewood mistake; it hisses, smokes, and gives up a fraction of its 24 to 26 MMBTU. Stack a year ahead or buy oak already seasoned.

The best-value stack is not one species. Load a splittable, quick-lighting wood like lodgepole pine at 21.1 MMBTU or birch at 20.8 to establish the fire fast, then add dense oak or hickory once it is hot for the long haul.^[1] This lets you spend hardwood money only where it pays off, on sustained heat, while cheaper local softwood does the lighting work.