Home › Wood pellet calculator
Wood Pellet Calculator
Work out how many bags your pellet stove goes through a day, how many tons to order for the winter, and what it will cost. Start from your stove's burn rate, or from the oil or propane you want pellets to replace.
How the estimate works
From the burn rate
Every pellet stove manual lists a burn rate range in pounds per hour, from its lowest to its highest setting. Multiply your typical rate by the hours the stove runs each day to get pounds per day, then divide by the bag weight.
For the stove presets, low and high are the ends of the manufacturer's range and medium is the midpoint. The typical-stove preset uses 1.5, 3 and 4.5 lb per hour, a span that covers most freestanding stoves. Your average over a whole season will sit below your midwinter rate, because fall and spring need less heat. If you only know your cold-weather rate, shave 15–25% off for a season estimate, or shorten the season.
From the fuel you'd replace
If you know how much oil or propane you burn, the calculator works out the heat your house actually used and how many pounds of pellets would deliver the same heat:
Example: 500 gallons of oil a winter in an 80% efficient boiler is 55.4 million Btu of heat. At 8,250 Btu per pound and 75% stove efficiency, that is about 8,950 lb, or 4.5 tons (224 bags). In practice a single stove rarely heats a whole house evenly, so pellets often cover 50–80% of the load while the boiler handles far rooms and hot water. Set the share accordingly.
Energy in a ton of pellets
Oregon State University Extension uses 16.5 million Btu per ton (8,250 Btu per pound) for good-quality pellets at 5–10% moisture, and we use the same figure. Premium softwood pellets can be a little higher; cheap or damp pellets lower and with more ash. As a check on stove efficiency: Englander rates the Evolution 25-EP at 25,100 Btu per hour of heat output at its 3.9 lb per hour top burn rate, which is about 78% of the pellets' energy, right in EPA's typical range.
Buying and storing pellets
Pellets are sold by the bag or by the ton, usually 50 bags of 40 lb on a pallet. Buying by the ton in late summer is usually cheapest, and running short in February, when stores sell out, is expensive. Store bags off the floor and under cover. Pellets that get wet swell and crumble, and damp pellets burn poorly and can jam the auger. Order a little more than the estimate (10% is a sensible buffer) and carry the extra into next season.
A pellet stove also needs electricity to run its auger and fans, so it won't heat the house in a power outage unless it has battery or generator backup.
Frequently asked questions
How many bags of wood pellets per day is normal?
Running around the clock, most pellet stoves burn about 1 to 2 bags (40 to 80 lb) a day in typical winter weather. On low that can drop under one bag; on high in a cold snap it can reach 2.5 to 3 bags.
How long does a 40 lb bag of pellets last?
About 10 to 40 hours. At 1 lb per hour (a low setting) a bag lasts 40 hours; at 4 lb per hour (high) it lasts 10 hours. The Englander 25-PDVC, for example, burns 2.2 to 3.8 lb per hour, or 10.5 to 18 hours a bag.
How many tons of pellets do I need for a winter?
As a main heat source, often 3 to 5 tons in a cold climate. As a supplement in the evenings, 1 to 2 tons. Use the calculator with your stove's burn rate and hours, or with the oil or propane you are replacing.
How many bags are in a ton of pellets?
Fifty 40 lb bags make one ton (2,000 lb). Pellets are usually sold by the ton on a pallet of 50 bags.
Are pellets cheaper than oil?
Often, but it depends on local prices. At 16.5 million Btu per ton and 75% stove efficiency, a $350 ton costs about $28 per million Btu of heat delivered, versus about $31 for oil at $3.48 a gallon in an 80% efficient boiler. Compare your own prices with the fuel cost calculator.
Sources
- Englander, 25-PDVC installation & operation manual: burn rate 2.2–3.8 lb/hr, 40 lb hopper; Evolution 25-EP manual: burn rate 1.6–3.9 lb/hr, heat output 10,700–25,100 Btu/hr.
- U.S. EPA Burnwise, Pellet stoves: typical efficiency 70–83%.
- Oregon State University Extension, Home Heating Fuels: Should I switch to firewood or wood pellets?: 16.5 million Btu per ton.
- EIA, Energy units: heating oil 138,500 and propane 91,452 Btu per gallon.
Last reviewed October 25, 2026. Estimates only; see the disclaimer.