Wood Pellet Calculator
Find how many 40-lb bags of wood pellets your stove will burn this winter, what they will cost, and how much it goes through on a midwinter day.
How many bags you go through depends less on the stove than on the space it heats, how cold your winters get and how much of the heating it does. A stove that carries the whole house in a cold climate can burn three to six tons a winter; one that takes the chill off a room, a small fraction of that.
Your home
The space the stove heats and the kind of winters you get.
Square feet the stove heats
The space the pellet stove actually keeps warm: the whole house if it heats it all, or just the main floor or a room or two.
Your winters
How much of your heat is pellets?
Pick the closest. A stove that runs all winter uses about four times what a weekend fire does.
Price per 40-lb bag
Most stores charge about $6 to $10 a bag; less by the ton.
Pellets for the winter
About 145 bags
40-lb bags, about 2.9 tons
A ton is a pallet of 50 forty-pound bags, usually cheaper per bag. The coldest days burn more than a midwinter average, and a drafty house more than this. 2026 figures.
💡About this calculator▼
Running out of pellets in February is a cold way to learn how much your stove burns. A stove that heats a whole house in a cold climate can go through several tons a winter, while one that takes the chill off the living room on weekends might need a few dozen bags.
This works it out from three things you know: how much space the stove heats, how cold your winters are, and how much of your heating it does. You get the bags to buy for the season, about how many tons that is, what it will cost at your price per bag, and how much the stove burns on a midwinter day.
Built on the same heating figures as our firewood calculator, so if you're weighing pellets against firewood, the two compare like for like.
How much heat the space needs. The calculator starts from the federal government's survey of home energy use: how much fuel homes burn for heating per square foot in each kind of climate. A cold climate takes about 29,900 Btu of fuel per heated square foot over a winter, a moderate one about 19,300 and a mild one about 11,500. That's multiplied by the space the stove heats and the share of the heating it does.
Turned into pellets. Those survey figures are fuel burned in a typical furnace, about 80% efficient. A pellet stove runs about 75% (certified stoves usually rate 70% to 83%), so it needs a little more fuel for the same heat. Good pellets hold about 8,250 Btu per pound, so each 40-lb bag holds about 330,000 Btu. A ton is a pallet of 50 bags.
A day in midwinter. A winter month takes about 17% of the season's heating, so a midwinter day is that share spread over 30 days. The coldest days burn more.
Worked example. A stove heating 1,500 square feet as the main heat in a cold climate: 1,500 × 29,900 = 44.9 million Btu, adjusted to the pellet stove = 47.8 million Btu, ÷ 8,250 = about 5,800 pounds, or 145 bags, 2.9 tons. At $8 a bag, about $1,160 for the winter, and about 33 pounds on a midwinter day.
📐How it's calculated▼
Pounds = square feet × heat per square foot × share × (0.80 ÷ 0.75) ÷ 8,250.
Heat per square foot: cold 29,900 Btu, moderate 19,300, mild 11,500. Share: main heat 1, about half 0.5, evenings and weekends 0.25.
Bags = pounds ÷ 40. Tons = bags ÷ 50. Cost = bags × price. A midwinter day = bags × 0.17 ÷ 30.
1,500 sq ft, cold, main heat, $8 a bag: about 145 bags, 2.9 tons, $1,160, about 33 lb a day in midwinter. 2,000 sq ft: about 195 bags, 3.9 tons, about a bag a day.
📎Sources:U.S. EIA — Residential Energy Consumption Survey 2020, space-heating energy by climate,New Hampshire Department of Energy — Wood pellet heat value and seasonal use,U.S. EPA — Pellet stoves (efficiency of certified stoves)
🔍Finding your inputs▼
Square feet the stove heats: The space the pellet stove actually keeps warm. The whole house if it heats it all; just the main floor, or a room or two, if that's what it reaches.
Your winters: Cold for the Northeast, Upper Midwest and mountains; moderate for the Mid-Atlantic, lower Midwest and Northwest; mild for the South, Southwest and coastal California.
How much of your heat is pellets? Main heat if the stove runs all winter and the furnace rarely does; about half if the furnace does the rest; evenings and weekends for a stove that takes the chill off.
Price per 40-lb bag: What you pay a bag. Most stores charge about $6 to $10, and less when you buy by the ton.
⚠️Special situations▼
My house is old and drafty
Plan on more. The heating figures are the average for homes in your climate, and a drafty older house can need half again as much. Buying an extra ton early is usually cheaper than running short in late winter.
Hardwood or softwood pellets?
Either gives about the same heat per bag. Once wood is ground and pressed into pellets, the density is roughly the same, and softwood pellets can even run a little higher because of their resins. Look for a quality certification on the bag rather than the wood type.
Should I buy by the bag or by the ton?
By the ton is usually cheaper per bag: a ton is a pallet of 50 forty-pound bags. If the calculator says 150 bags, that is three tons.
❓Common questions▼
How many bags of pellets will I use in a winter?
It depends on the space and the climate. A stove that heats 1,500 square feet as the main heat in a cold climate burns about 145 forty-pound bags, about 3 tons. In a moderate climate, about 95 bags. A stove used only on evenings and weekends needs about a quarter as much.
How many tons of pellets do I need for the winter?
About 3 tons for a stove heating 1,500 square feet as the main heat in a cold climate, and about 4 tons for 2,000 square feet. A large or drafty house in a cold region can take 5 or 6 tons.
How long does a 40 lb bag of pellets last?
About a day in midwinter for a stove heating around 2,000 square feet as the main heat in a cold climate, and longer for smaller spaces or milder weather. A stove heating 1,500 square feet burns about 33 pounds on a midwinter day.
How much does it cost to heat with a pellet stove?
At $8 a bag, about $1,160 a winter for a stove heating 1,500 square feet as the main heat in a cold climate, or roughly $200 in a midwinter month. Buying by the ton usually lowers the price per bag.
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