What moisture basis is used for these BTU ratings?

The table follows Penn State Extension Table 1, which assumes air-dried wood at 20% moisture content. Wood that is wetter or drier than that basis will not match the listed heat value.

For this calculator, one full cord is 128 cubic feet of stacked wood, conventionally represented as a stack 4 ft high × 4 ft wide × 8 ft long. Enter fractions of a full cord when you have less.

Why does this tool avoid a fixed face cord multiplier?

A face cord (or rick) describes the face of a stack but does not fix the piece length or stack depth. Convert your stack to a fraction of 128 cubic feet before using the estimator.

How is cost per usable million BTU calculated?

Cost per usable MMBTU equals total price divided by usable MMBTU. Usable MMBTU is the listed gross MMBTU per cord multiplied by the number of cords and the efficiency percentage you enter.

Why can other firewood charts show different values?

Penn State Extension notes that heating values can differ because reports use different methods and test different individual trees. This page keeps every table row on the same cited basis instead of mixing sources.

Firewood BTU Reference Chart & Heating Estimator

Compare 16 Penn State firewood heat values on an air-dried, 20%-moisture basis and estimate gross heat, usable heat, equivalent continuous heating time, and cost per usable MMBTU.

Firewood Heat Value by Species

Penn State Extension Table 1 · Air-dried basis (~20% moisture)

Firewood species heat content in million BTUs per standard cord
Species	Botanical Taxon	MMBTU / Cord

Primary source: Penn State Extension, Heating with Wood: An Introduction (Table 1). Values are MMBTU per full cord of air-dried wood at an assumed 20% moisture content.

Botanical Note: Source nomenclature and historical orthography are faithfully preserved from the primary reference publication.

Standard Units & Combustion Limitations

Standard Cord Volume

This estimator treats one full cord as 128 cu ft of stacked wood, conventionally represented as 4 ft × 4 ft × 8 ft.

Face Cords & Ricks

A face cord or rick does not specify stack depth. Measure the stacked cubic feet and divide by 128 before entering a quantity.

Moisture Limitation

The table assumes 20% moisture. This calculator does not invent a correction for wetter or drier wood; measure moisture and treat mismatched values as estimates.

Continuous Demand Basis

Heating hours indicate steady-state continuous thermal demand matching the specified BTU/hr rate. Actual home cycles fluctuate with outdoor temperature and thermostat setpoints.

Heating & Fuel Cost Estimator

Model delivered thermal output and cost per million BTU

Species Selection

Full Cords

128 cu ft standard units

Efficiency (%)

Use your appliance rating

Continuous delivered heat demand (BTU/hr)

Continuous heat rate

Price / Cord ($)

For cost/MMBTU calc

Summary

Compare 16 Penn State firewood heat values on an air-dried, 20%-moisture basis and estimate gross heat, usable heat, equivalent continuous heating time, and cost per usable MMBTU.

How it works

Search or sort the species table by common name, scientific name, or heat content in MMBTU per full cord.
Select a species in the estimator and specify your quantity of full cords (128 cubic feet stacked).
Enter your appliance efficiency percentage and continuous delivered heat demand rate (BTU/hr).
Optionally provide price per full cord to compute fuel cost per million usable BTUs.
Review gross heat, delivered usable heat, operating hours at target demand, and heating economics.

Use cases

Compare heat density across firewood species on an identical 20% moisture baseline.
Calculate net usable heat after accounting for modern stove or boiler efficiency.
Determine continuous operating hours supported by a wood stack at design heat loss.
Evaluate firewood market quotes by comparing true cost per delivered million BTU.

Frequently Asked Questions

Last updated: 2026-09-19 · Reviewed by Nham Vu