Shopping

Compare unit price, not pack price

Shopping bag with fresh vegetables on wooden table, illustrative depiction of shopping tips category

The unit price per kilo or liter reveals the real price.

$6-11 per week 5 min Updated 2026-04-22

Contents

  1. How to do it
  2. Common mistakes
  3. Bottom line

Bulk packs look cheaper, they often aren't. The trick: don't look at the total price, look at the unit price per 100 grams. That's how you spot rip-off packaging and actually save money.

Step by step

Manufacturers hide price increases through psychological tricks: bigger box, less content. Example: 1 kg muesli for 8 € looks pricier than 500 g for 4.50 €. But 500 g costs per 100 g: 0.90 €, while the big pack only costs 0.80 €. Stores are required to show the unit price (usually fine print). Anyone who compares that instead of the total price saves an average of 25%, without sacrificing quality or quantity. Focus on shelf-stable basics with long shelf life, rice, pasta, legumes, flour, coffee, olive oil. That's where the difference between small and bulk packs is often 20-40%. With fresh products, bulk buying only pays off if you're sure you'll use it before it spoils.

Source: Verbraucherzentrale Bundesverband, 25% of bulk packages are MORE expensive per unit, unit price comparison is essential

Step by step

  1. Read the unit priceLook at the white price label on the shelf. There's the price per 100 g or liter. Write it down for your favorite item.
  2. Compare all package sizesNot just 500 g vs. 1 kg, check 3-packs, bulk boxes, and special packs too. Sometimes the mid-size is surprisingly cheaper.
  3. Check promotional pricesPromos change the rules: a normally pricey pack suddenly cheaper. The comparison changes every day, your notes get outdated fast.
  4. Check shelf lifeBulk packs only make sense if you'll actually use them. Expired muesli is expensive waste. For couples and singles: small packs often work better.
  5. Reality-check storage capacityPasta, canned goods, dried fruit: good for storage, bulk makes sense. Fresh products: normal shelf life or split with a friend.

Worked example

Before: Ms. M. buys 1.5 kg muesli for 12 € instinctively (= 0.80 €/100g). Thinks: economical.
After: With a unit price check, she discovers: 750 g for 5.40 € (= 0.72 €/100g) is 10% cheaper. Annual savings: ~30 €.

How much does your annual food shopping cost? Calculate your average.

Keywords and context

This tip is written for households that want to cut energy and cost-of-living spending concretely. It complements the other measures in the same category and has the greatest effect when combined with them.

shoppingsave energyhouseholdcut coststipefficiency
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Frequently asked questions

Is bulk buying really more sustainable?
Yes, less packaging waste per item, fewer shopping trips. But only if you actually use it. Moldy food is expensive waste.
How do I remember all these unit prices?
Keep a notebook at the store, take photos of shelf tags on your phone, or use an app like smart shopping list. After 3-4 shopping trips, you'll know your top 10 by heart.
Are there cases where bulk is more expensive?
Yes: organic products in health stores (packaging is expensive), regional specialties, and overstock items. Keeping your eyes open is worth it.
How do I combine this with other tips?
Effects stack: the more tips applied, the higher the saving up to a cap.

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