Worked exampleExported from Calvance
3D Printing Material & Electricity
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View template and methodPackage Unit Price Comparison
Compare two multipack offers by total items and cost per item. Includes a worked example, price-change comparison and an editable Calvance canvas.
Worked exampleExported from Calvance
Exported by the iOS App After importing, edit the numbers in Calvance.
When to use it
Compare two offers for the same type and size of countable item, such as household supplies. Enter the number of packs, items per pack and total amount payable for each offer. This page explains the calculation and provides a downloadable canvas; it is not an online shopping-price feed. All USD prices below are independent simulated examples.
Inputs
USD
| Inputs | Default |
|---|---|
| Packs in offer A | 3 |
| Items per pack in A | 24 |
| Total payable for A | 18 |
| Packs in offer B | 4 |
| Items per pack in B | 24 |
| Total payable for B | 22.08 |
Calculation method
First multiply packs by items per pack for each offer. Divide each total payable by its own item count. Subtract B’s unit price from A’s: a positive exact difference means B is cheaper per item; a negative one means A is cheaper. A contains 3 × 24 = 72 items for USD 18, or USD 0.25 each. B contains 4 × 24 = 96 items for USD 22.08, or USD 0.23 each. B saves USD 0.02 per item but requires USD 4.08 more in total and buys 24 extra items.
3 [Packs in offer A] × 24 [Items per pack in A] → Total items in A
4 [Packs in offer B] × 24 [Items per pack in B] → Total items in B
18 [Total payable for A]/Total items in A → Cost per item in A
22.08 [Total payable for B]/Total items in B → Cost per item in B
Cost per item in A - Cost per item in B → Unit price difference (A − B)
Change one input
Change only B’s total from USD 22.08 to USD 26.88. Its 96 items now cost USD 0.28 each. A stays at USD 0.25 and the difference becomes −USD 0.03 per item: A is now cheaper per item. Pack counts and contents are independent inputs even when the defaults match.
| Result | Default | Changed |
|---|---|---|
| Total items in A | 72 | 72 |
| Total items in B | 96 | 96 |
| Cost per item in A | 0.25 | 0.25 |
| Cost per item in B | 0.23 | 0.28 |
| Unit price difference (A − B) | 0.02 | -0.03 |
Results are displayed to at most two decimal places; later formulas use unrounded values.
Scope and limits
- Compare equivalent individual items using one currency and consistent total costs.
- Exact A − B > 0: B costs less per item; < 0: A costs less.
- Pack counts and items per pack: positive integers. Total payable ≥ 0.
A lower unit price does not imply a lower checkout total or a better purchase for your needs. Check size, quality, usable quantity, storage and expiry separately. The canvas compares counts, not grams, litres or mixed bundles. Discounts, shipping and taxes are not computed automatically: include applicable amounts consistently in both totals. It does not model returns, resale or future promotions.
Download and import into Calvance to edit the numbers. The canvas does not reject every invalid input; check the stated ranges.
Common questions
Which price should I enter?
Use the total payable for all packs in that offer, after discounts that actually apply. Treat shipping and tax consistently for A and B. Do not enter one pack’s price when the pack count is greater than one.
Does a displayed difference of zero mean the prices are identical?
Not necessarily. A small difference may round to zero at two decimal places. Increase the result’s decimal precision in the App to inspect close prices. Only an exact zero means equal unit prices.
Is the larger bundle always better value?
No. Compare both unit prices and the amount you must pay. In the default example B is cheaper per item but costs more overall. Buying more than you can use may erase the apparent saving.
How to import your template
- Save the file. Choose Download template and save the .calvx file to Files on your iPhone or iPad. From a computer, you can send it to your device with AirDrop.
- Open Import. In All Canvases in Calvance, tap the add button to open the template screen, then choose Import.
- Choose the file. Select the saved .calvx file to create your own canvas. Importing uses one canvas from your allowance.
- Edit and check. Check the results against the worked example, then add your numbers. Duplicate the canvas to keep different versions.
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