THE NUMBERS, EXPLAINED
How to use this calculator.
Constant daily demand, no receipts, earliest expiry first. Selling days are supplied approved windows; no shelf-life determination.
Start with your inputs
Enter units remaining by expiry cohort, whole selling days remaining by cohort, expected daily demand (units). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Units remaining by expiry cohort | 40,60 |
| Whole selling days remaining by cohort | 2,4 |
| Expected daily demand (units) | 20 |
A worked example
With the example inputs above, projected units sold is 80. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Projected units sold | 80 |
| Units exposed to expiry | 20 |
How this is calculated
Projected units sold
Allocate cumulative demand to earliest-expiry cohorts first.
Units exposed to expiry
Subtract projected FEFO sales from current stock.
Symbols and units
- a
- Units remaining by expiry cohort
- b
- Whole selling days remaining by cohort
- c
- Expected daily demand (units)
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Assumptions and limits
Constant daily demand, no receipts, earliest expiry first. Selling days are supplied approved windows; no shelf-life determination.
Calculations use the values you enter. Blank or invalid inputs show an error instead of silently substituting zero. Results are displayed to useful precision; calculations retain the underlying numeric precision.
Questions about this tool
What does the result tell me?
Projected units sold; Units exposed to expiry. The result applies to the method and inputs described above. Check the units and assumptions before using it in a decision.
Why might another calculator differ?
Differences in units, rounding, timing or model definitions can produce different answers. Compare the input definitions and the method, rather than only the final number. For this tool: Constant daily demand, no receipts, earliest expiry first. Selling days are supplied approved windows; no shelf-life determination.
Are my inputs stored or sent to AI?
Calculations on this page happen in your browser. The separate AI question finder sends its submitted conversation to OpenAI; these calculator fields are not sent. Favourites and recent tool names are stored locally. A shared link contains the inputs you choose to include.
Further reading
OpenStax: Describe and Identify Cost Drivers ↗
Background reading; this does not imply endorsement or independent review of SumFizz.
Review status
Software example and browser checks are recorded in our quality report. No external expert review is claimed. Created with coding assistance; calculations run as ordinary browser code.
Read the quality report →