How do you all estimate your firewood in cords/BTUs?

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Matthew7

New Member
Jul 28, 2025
2
Maine
I’ve been working on a little firewood measuring calculator tool, but I’m running into one question I can’t quite settle:

When adjusting for stacking factor (tight vs. loose stacking), I’ve been using these ranges:
  • Loose stacking: 70–75% of full volume
  • Average stacking: 80–85%
  • Tight stacking: 90–95%
Do those numbers seem right to you folks who’ve stacked and burned a lot of wood? Or do you find your actual usable wood volume comes out different?
I’m trying to make my calculator as accurate as possible, so any real-world input would help a ton. Here’s the tool if you want to see the whole calculation breakdown: https://woodstovehub.com/cord-of-wood-calculator/
Also curious, how do you factor in moisture content when estimating BTUs? I’ve been applying a percentage reduction based on MC, but maybe there’s a better approach.
 

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Thanks for sharing, I hadn’t seen this calculator before!
Looks like it’s solid for just figuring cords from measurements, but I was kinda messing around with extra stuff like BTU estimates by species, adjusting for moisture, how tight the stack is, and even a rough cost value. Mostly for my own curiosity (and because I overthink firewood way too much 😅).
 
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Reactions: bigealta
Many years ago, my Father-in-Law told me that when stacking firewood, make it squirrel tight
mouse loose for best drying and Max BTU . That's the way I have done it for the last 55 years
no matter how you stack it, a cord of firewood is 8x8x4. Here is a chart already done for you