How much does a bag of wood pellets weigh? 15 kg, and why

Short answer: the standard bag of wood pellets weighs 15 kg. Bags of 10, 20 and 25 kg exist, as do big bags of roughly a tonne, but every bagged offer in the shops we track is a fifteen. The rest of this article covers what the short answer leaves out: how many bags make a tonne, how much room one bag takes, and how to turn a bag price into the price you actually pay.

Why 15 kg

Fifteen kilograms is the compromise the whole market settled on: a bag you can carry in one hand, tip into a hopper without help, and stack on a pallet in even layers. The shop guides collected under this article all describe 15 kg as the industry standard, with 20 and 25 kg bags as a variant for industrial boiler rooms or people who prefer fewer trips, and 10 kg bags for those who would rather not lift.

From our own catalogue. We track four bagged offers (OBI, Castorama, Dremus, CSTB) — all 15 kg. Not a single ten, twenty or twenty-five. If you buy online or at a DIY chain, assuming "bag = 15 kg" is safe, but check the label anyway: the per-tonne conversion hangs on that one number.

How many bags make a tonne

The arithmetic is simple; the result just isn't round:

Bag weight	Bags per tonne	Typical pallet
15 kg	66.7 (in practice 66 or 67)	65 bags = 975 kg, 66 = 990 kg, 67 = 1005 kg, 70 = 1050 kg
10 kg	100	about 96 bags = 960 kg
20 kg	50	50 bags = 1000 kg
25 kg	40	40 bags = 1000 kg

That unroundness is why a "pallet" weighs 975, 990, 1005 or 1050 kg depending on the seller — it is simply 65, 66, 67 or 70 fifteens. What that does to the price is set out in the article on pallet weight.

How much room a bag takes

Pellets are not dense like stone. The ENplus standard requires a bulk density of 600–750 kg/m³ (the thresholds are quoted in our class table). Fifteen kilograms therefore occupies 20–25 litres — roughly a builder's bucket. For reference, the 15 kg Olimp bag listed by Bricomarché measures 39 × 15 × 55 cm.

The practical consequence: a pallet of 65 bags is about 1 m² of floor and 160–180 cm of height. A season's 4 tonnes is four such pallets — where and how to keep them dry is a separate topic.

Turning a bag price into a price per tonne

This is the part that matters, because a "per bag" price is small and therefore looks harmless. The formula:

bag price ÷ bag weight × 1000 = złoty per tonne

An example from our table: a 15 kg bag of Beskid at OBI last cost 37.99 zł. That is 37.99 ÷ 15 × 1000 = 2,533 zł/t. The same class A1 by the pallet from online sellers is often several hundred złoty per tonne cheaper — we make that comparison daily in the price table, where every offer, bagged or palletised, is shown in zł/t.

That doesn't make bags a bad choice. Buying five bags to finish off March, you pay for convenience and for not committing — and that is often sensible. When bags make sense and when they don't is worked through in bags or pallet.

What to watch for

1. Net weight on the label. A bag holds 15 kg of pellets; the film adds a few dozen grams not worth counting — but check the shop states the fuel mass, not "approx. 15 kg".
2. Fines at the bottom. The standard allows at most 0.5% fines (particles under 3.15 mm) in bags. A bag with a handful of sawdust at the bottom may have been transported badly — how to judge it is in how to recognise good pellets.
3. Price per bag versus price per kilogram. DIY chains often show both. Price per kilogram times 1000 is the price per tonne — the quickest way to compare with a pallet offer.

Summary

A bag is 15 kg, a tonne is 66–67 bags, and a pallet is 65–70 bags depending on the shop. The only number that truly lets you compare a bag with a pallet and one shop with another is złoty per tonne — and that is the only one we show.

Sources

• Dremet.pl — "Ile waży worek pelletu?" — 15 kg as the standard, 10/20/25 kg variants and 1000–1200 kg big bags, pallet conversion table (Polish).
• Klima-cool.pl — "Ile waży worek pelletu i od czego to zależy?" — bags-per-tonne conversions (66 × 15 kg = 990 kg, 50 × 20 kg, 40 × 25 kg), 960–1000 kg pallets (Polish).
• Cosmogas.pl — "Ile waży worek pelletu?" — bag-size use table, 65–70 bag pallets (Polish).
• Bricomarché — Pellet OLIMP EN plus A1 15 kg Stelmet — bag dimensions 39 × 15 × 55 cm.
• ENplus® ST 1001:2022 — bulk density 600–750 kg/m³ and the fines limit for bags.
• Pack weights of tracked offers: our own catalogue, set by hand from real product pages — method (Polish).