Aluminium foil is sold two ways, and both hide short foil. 18-micron is sold by weight; 11-micron is sold by metres. A "1 kg roll" is gross weight — foil plus the cardboard core — and sellers inflate the core to ship you less foil. An honest 1 kg roll is ~1,000 g of foil on a ~100 g core; a cheated one puts 300 g of core inside, so you get only 700 g of actual foil for the same price. Here's how to check what you're actually buying.
Where the trick lives: gross vs net
Foil rolls are quoted as "1 kg." Buyers assume that's foil. It isn't — it's the whole roll on the weighing scale, foil plus core. The foil is what you cook with; the core is cardboard you throw away. Push more weight into the core and the headline stays "1 kg" while the foil you actually get drops.
| Honest roll (SGS standard) | Cheated market roll | |
|---|---|---|
| Gross (whole roll) | ~1,100 g | 1,000 g |
| Core (cardboard) | ~100 g | 300 g |
| Actual foil | 1,000 g | 700 g |
Same "1 kg" on the label. One gives you 1,000 g of foil, the other 700 g — a 30% short-fill hiding in the cardboard. At a busy kitchen's foil consumption that gap adds up fast, and you never see it because you never weigh the core.
How to verify it yourself — the weigh-the-core method
Don't trust the label; measure it. It takes one roll and a kitchen scale:
- Weigh the sealed roll before use — that's your gross weight. Write it down.
- Use the roll normally until the foil is finished.
- Weigh the empty core — the bare cardboard tube left behind.
- Subtract: gross minus core = actual foil weight you paid for.
- Compute the true rate: price ÷ actual foil weight = real ₹ per kg of foil.
Now compare suppliers on that real ₹/kg-of-foil number, not on the "1 kg roll" sticker price. A roll that looks ₹20 cheaper but carries 300 g of core is the expensive one once you do this. Run the test once on a new supplier and you'll know exactly who's padding the core.
The other trap: weight vs metres
18-micron foil is sold by weight (grams/kg). 11-micron foil is sold by length (metres). They're not the same purchase and you can't compare them head-to-head on price. If a quote switches units on you — grams for one roll, metres for another — that's your signal to slow down and ask which micron and which unit you're actually being quoted. 72 m foil is its own category; price it against other length-sold rolls, not against weight-sold ones.
To compare two foils honestly, line up
- Micron (11 or 18) — thickness. Thinner tears and pinholes more easily.
- Unit of sale (weight vs metres) — never compare across the two.
- Actual foil weight (gross minus core) — the number that matters.
- True ₹/kg of foil — computed from actual foil weight, not gross.
Match on all four and the real price falls out. Skip the core weight and you're comparing sticker prices that mean nothing.
What to do next
- See our food-packaging range, including foil rolls quoted honestly on net foil weight and core.
- Buying foil for a kitchen? Weigh your current supplier's core using the method above, then send us the roll you're using — we'll quote the same spec on true ₹/kg of foil so you can compare apples to apples.