The big number on a shelf label is the pack price. The small number – price per kg, per litre or per item – is the one that tells you what's actually cheaper.
Why it matters
- A bigger pack isn't always better value. Check the unit price.
- Multibuys can look generous but work out the same as the single price – or worse – once you compare per unit.
- Different supermarkets use slightly different pack sizes (400g vs 410g vs 420g), which makes pack prices hard to compare directly.
Three quick tips
- Compare unit prices across own-label tiers too – "standard" own-label is often within a few pence of "value" per kg.
- Watch out for unit prices quoted per 100g on one item and per kg on another.
- For things you'll use anyway, a genuine multibuy is a saving – but only if you'd have bought the extra.
TillTotal converts pack sizes automatically, so when you compare a basket the stores are always compared on the same quantity.