Unit price comparator
Calculators
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About this tool
Compare 2–20 offers in one currency and quantity dimension. Enter price per pack, packs purchased, items per pack and quantity per item. Inspect the effective total, normalized quantity, exact formulas and unit-price ranking.
Common uses
- Compare a multipack with a larger single package without losing the inner-item count.
- Account for percentage discounts, a whole-offer coupon and shipping before choosing the lower unit price.
How to use it
- 1.Choose mass (mg/g/kg), volume (mL/L) or count (piece) and a shared three-uppercase-letter currency label.
- 2.Enter at least two offers; apply percentage discount to merchandise first, then subtract a coupon, then add shipping once. Compare.
- 3.Review formulas and ranks, then optionally export JSON with original inputs, exact fractions and rounded amounts.
Limits and notes
- 2–20 offers; decimal inputs: up to 12 integer and 6 fractional digits, period only. Packs/items: integers 1–1000000. Names: 80 characters. JSON: 128 KiB maximum.
- Enter all offers in the same currency and tax basis. This label performs no currency conversion, tax calculation or live-price lookup. Coupon must not exceed merchandise after percentage discount; quantity must be positive. Mass, volume and count cannot be mixed. Changing the quantity group resets units; check each entered amount again.
- Shown amounts round half up to 6 decimals; ranking uses exact fractions. Equal exact prices share a rank, retaining entry order; subsequent ranks may skip. Positive quantities or prices can display as 0.000000. Expand formulas for exact values.
- All calculations are browser-local; no input persistence, upload or live prices. No cross-dimension conversion, density assumption, conditional promotion rules or currency minor-unit rounding. JSON contains entered names and all offer values; review before sharing. Edits, locale changes and leaving discard results. Changing dimension resets units without converting quantities.
Frequently asked questions
How are discounts and shipping applied?
Each offer: price per pack × packs × (1 − discount % / 100) − whole-offer coupon + shipping once. Quantity: amount per item × items per pack × packs. Shipping receives no discount.
Can USD and JPY or mass and volume be mixed?
Enter all offers in the same currency and tax basis. This label performs no currency conversion, tax calculation or live-price lookup. Coupon must not exceed merchandise after percentage discount; quantity must be positive. Mass, volume and count cannot be mixed. Changing the quantity group resets units; check each entered amount again.
Why can two identical displayed prices have different ranks?
Shown amounts round half up to 6 decimals; ranking uses exact fractions. Equal exact prices share a rank, retaining entry order; subsequent ranks may skip. Positive quantities or prices can display as 0.000000. Expand formulas for exact values.
What is included in the JSON?
Original offer strings, ordinal source rows, rank, reduced exact fractions, 6-decimal rounded values and plain-text formulas. No executable formulas, CSV or remote lookup.