Comparing Bundles With Different Quantities Without Inventing a Unit Price

Two bundles sit side by side. One has twelve items, the other eight plus a free accessory. A tempting comparison row says Price per item, and a tempting shortcut fills blanks with zero. Both can mislead. This article proposes a comparison page workflow that stays truthful when quantities differ and some data is missing. It is a proposed editorial example using invented products, not an observed result.

The artifact: a comparison table with explicit cells

Each bundle is a column. Each row is a fact the shopper may care about. Every cell holds one of four things: a value, Not included, Not stated, or Not comparable.

Not included means the bundle does not contain the item. It is a known fact.
Not stated means you do not have the information. It is unknown.
Not comparable means the items differ in a way a single number would hide.

Zero is a real value only when you mean exactly none, such as 0 accessories.

Inputs

Use a hypothetical public sample: a made up tea sampler. Bundle A: 12 sachets, 3 flavours, a tin. Bundle B: 8 sachets, 2 flavours, no tin, plus a strainer. Bundle C: 20 sachets, flavours Not stated, tin Not stated. For each bundle you need the bundle price, the quantity of each included item, and the unit each quantity uses.

Decision branches

Same item and same unit in every compared bundle: a quantity row is safe, for example Sachets: 12, 8, 20.
Item present in some bundles only: show Not included in the others, and place the extra item in its own row, such as Strainer.
Quantity not stated: show Not stated. Do not compute anything from that bundle for that row.
Unit price: calculate and display it only if every figure it uses is stated, the unit is identical, and the bundle contains one comparable kind of item. Otherwise show Not comparable with a short reason. Whether to show unit prices at all is a business choice; the page works without them.
Mixed contents where a free extra exists: describe the extra in words, and do not subtract its imagined value from the price.

Stop conditions

Stop publishing a comparison if fewer than two bundles share any stated attribute, because the table would be mostly unknowns. Show the bundles as separate descriptions instead. Also stop if two bundles use units that cannot be converted by a statement you can defend, such as sachets against grams with no sachet weight given.

Worked example

Rows: Bundle price, Sachets, Flavours, Tin, Strainer, Price per sachet.

A: price shown, 12, 3, Included, Not included, calculated from price and 12.
B: price shown, 8, 2, Not included, Included, calculated from price and 8, with a note that the strainer is extra.
C: price shown, 20, Not stated, Not stated, Not included, calculated from price and 20.

The per sachet row appears for all three because sachet counts and units are stated. A footnote says the figure ignores the tin and strainer. If Bundle C's sachet count were missing, its cell would read Not comparable and the others would still show.

Wording and layout notes

Put the unit in the row label, not only in cells. Keep the first column fixed so labels stay visible when the table scrolls on a narrow screen. Avoid highlighting a Best value badge unless you can state the rule behind it; a badge implies a comparison you have not defined.

Avoid sorting rules that treat blanks as small numbers. If shoppers can sort by sachets, place Not stated entries at the end and say so.

Acceptance test

Run this with the three sample bundles and someone unfamiliar with the page.

Check every cell holds a value or one of the three labels. No empty cells and no unexplained zero.
Blank out Bundle C's sachet count. Confirm its cell changes to Not stated and its per sachet figure changes to Not comparable, with no effect on A or B.
Change Bundle B's unit to grams without a conversion. Confirm the unit price row stops showing a figure for B.
Sort by sachets. Confirm unknown entries sit last.
Ask the tester which bundle includes a tin and which does not. They should answer without hesitation, distinguishing Not included from Not stated.

The page passes if the tester never reads an unknown as a zero or a missing item as a free one.

Conclusion

A fair comparison is built from labelled facts. Say what is included, say what is unknown, and calculate only what the data supports.