Compare Bulk Packs at the Real Unit Price — Free, Before the Bulk Store Wins
Bulk buying is sold on the pack, not the unit price: the warehouse pack looks cheaper because it is bigger, and the store brand is quietly cheaper per unit while looking more expensive. The comparison takes ten seconds with the arithmetic done for you.
The proof surface
Free path: the tool computes locally in this browser with no key and no account. Where an AI step helps, any free chat assistant works — free tiers exist (Google AI Studio, Groq), but plans and limits change, so check the provider's own page. No third-party service is claimed here as verified: UNCONFIRMED — model has no browsing access this session.
Why the flat version breaks
Shelf labels show a unit price, but only for the size on that shelf and only in the unit the retailer chose. Comparing a 5 kg bag against four 1.2 kg bags, or a concentrated refill against a diluted bottle, needs one common unit and the quantity you actually use.
How to use the unit price comparison receipt in four passes
Kilograms, litres, washes, tablets — pick the unit you actually think in and convert all the offers to it. Concentrated detergent needs one extra step: convert to the number of washes the pack delivers, not its volume.
Member prices, coupons and multi-buys change the ranking completely. Run the list once at shelf prices, then run it again with the discounted price on the one pack that qualifies — the difference is usually smaller than the marketing implies.
The receipt sorts by unit price and prints how much more each pack costs for the same quantity. A gap of a few cents per kilogram is not worth a trip; a gap of half the price is.
Multiply the unit-price gap by your usage figure. Under a few dollars, buy whichever is more convenient; over the price of a month's supply, the storage and the trip are worth planning around.
SAMPLE DATA, NOT A VERIFIED CLAIM: the starter record is four flour packs from a warehouse trip, with a refill pouch that undercuts the bulk bag per kilogram. Replace these values with your own source before you rely on anything.
What breaks first
Comparing pack prices instead of unit prices
The bigger pack is almost always the bigger number on the shelf and often not the cheaper unit price. This is the single most common way a bulk store wins a comparison it should lose.
Ignoring spoilage on the cheapest unit price
Twelve kilograms of flour at the best unit price is not a saving if two of them go stale. Enter your real usage — the receipt will show the point where the cheap pack stops being cheap.
Mixing concentrated and ready-to-use products
A concentrated refill is not comparable to a diluted bottle by volume. Convert both to the number of uses or washes, or the ranking will be wrong in whichever direction the pack sizes run.
What you pay otherwise
| The usual route | What it leaves out | Cost |
|---|---|---|
| A warehouse membership | Annual fee to access a pack that is sometimes dearer per unit | $40–$65 a year |
| Buying the biggest pack by default | Cash tied up in stock and a share of it spoiled before use | the pack premium |
| A price-tracking app | Subscription for a comparison you can run on five offers in a minute | $3–$10 a month |
| This page + the free unit price comparison receipt | Computed in your tab, result on screen before you type anything | $0 |
Try the free unit price comparison receipt right here
Load the starter offers and change the usage figure to 5 to watch the bulk-pack saving shrink towards nothing.
FIRST-LOAD · sample record filed
Take it into the free unit price comparison receipt
The companion app runs the same logic with a numbered intake, three starter records, a stateful share link, the one-time printable layer, and the local history shelf.
Open the free unit price comparison receipt →Keep the work if you will use it again
The full ranked comparison: every pack's unit price, the per-pack gap and the saving across your usage, unlimited re-runs.
The on-screen result is free and complete. The one-time layer adds a tangible file you keep and the saved history that comes with it.
Boundary: This compares prices you enter; it does not verify shelf prices, loyalty terms or availability, and it does not account for storage, quality or spoilage beyond the usage figure you supply. Check current prices in store before buying in bulk.