Whole-pack order cost, usable supply, and demand coverageLive current inputs
Everyday Calculators
Price per Unit Budget Calculator
Choose whole case-pack quantities under budget, protected cash, order fees, tax, shipping, expected waste, demand, and storage limits.
Spendable budget —
Maximum affordable packs —
Packs required for demand —
Budget-and-storage feasible packs —
Recommended order cost —
Expected usable units —
Budgeted price per usable unit —
Demand coverage —
Integer affordability staircase
Whole-pack order cost, usable supply, and demand coverage
The staircase respects pack indivisibility, the one-time fee, per-pack delivery, the protected reserve, and storage capacity. The demand line shows the first order size that is operationally sufficient.
Live decision table
Whole-pack purchase schedule
Review cost, remaining cash, usable supply, and coverage for each feasible pack count.
| Packs | Order cost | Cash remaining | Usable units | Demand surplus/gap | Feasibility |
|---|
Constraint setup
Separate cash, demand, and storage
- Protect cash reserve first.
- Use whole-pack prices.
- Include per-order and per-pack costs.
- Enter physical storage capacity.
Integer logic
A fractional unit-price answer cannot place an order
The calculator rounds affordable packs down and required packs up. That asymmetry is essential for a realistic purchase decision.
Expected waste reduces the usable units delivered by every pack.
Calculation method
Solve budget, demand, and storage as separate integer constraints
Whole packs cannot be purchased fractionally. Budget determines the maximum count, usable demand determines the minimum count, and storage imposes a separate ceiling.
Detailed calculation process and general formulas
K = max(Budget - Reserve, 0)Variable_pack = Price x (1 + t) + Shipping_packN_afford = floor((K - Order_fee) / Variable_pack)Usable_pack = Units_pack x (1 - w)N_required = ceil(Demand / Usable_pack)N_feasible = min(N_afford, N_storage)Order_cost = Order_fee + N x Variable_pack Symbols, meanings, and units
- K
- spendable budget after reservecurrency
- Variable_pack
- taxed pack price plus per-pack shippingcurrency/pack
- N_afford
- maximum packs supported by spendable cashpacks
- Usable_pack
- expected usable units from one packunits/pack
- N_required
- minimum packs needed for demandpacks
- N_storage
- maximum packs storage can holdpacks
- N_feasible
- maximum packs allowed by budget and storagepacks
- Order_cost
- cash cost for selected whole packscurrency
The live worked calculation below substitutes the current inputs in formula order and reconciles the primary output with the result cards and visualization.
Coverage decision
The feasible maximum may still miss demand
If required packs exceed the smaller of budget and storage capacity, the order is under-covered. Reduce demand, add budget, improve yield, or source a different pack.
Surplus supply should be assessed against shelf life and carrying cost.
Procurement check
Verify the order before committing
- Confirm current pack price.
- Confirm shipping tiers.
- Check tax and minimum order.
- Check usable storage and shelf life.
Purchase-constraint review
Which constraint prevents demand coverage?
The model reports affordable, required, and storage-limited pack counts separately so an infeasible order has a visible cause.
Spendable cash
—Budget remaining after protecting reserve.
Affordable packs
—Whole packs supported after order and per-pack charges.
Required packs
—Whole packs needed after expected unusable loss.
Order unit cost
—Recommended order cost per expected usable unit.
Decision takeaway: Do not interpret a low per-unit price as affordable when the required whole-pack order exceeds cash or storage limits.
Practical applications
Decisions this calculator is designed to support
Bulk household consumables
A household tests whether five or six whole cases fit a $240 budget while preserving $20 and covering ninety usable units.
What the result clarifies: The staircase shows the exact cash and supply consequence of each additional case.
Small-workshop materials
A workshop has enough cash for bulk packs but limited dry storage and a recurring defect rate.
What the result clarifies: Storage and usable-yield constraints are tested independently from shelf price.
Worked example
Current-input substitution and reconciliation
This live example converts the cash ceiling into whole purchasable packs, protects the required leftover cash, and reconciles usable quantity after waste with the entered demand target.
Important note
This model uses expected average waste and does not optimize uncertain demand, holding cost, expiration, supplier lead time, or quantity discounts unless they are reflected in the entered pack price.
Choose the number of whole packs that fits a budget and meets usable demand FAQ
Why can recommended packs be below required packs?
The recommended feasible count is limited by cash and storage. When it is below demand requirements, the status reports a coverage gap.
Is the order fee charged at zero packs?
No. It is charged only when at least one pack is ordered.
How are quantity discounts handled?
Run separate scenarios using the pack price applicable to each pricing tier.
What if shipping is one flat fee?
Enter it as the one-time order fee and set per-pack shipping to zero.