THE NUMBERS, EXPLAINED
How to use this calculator.
Uniform deposit, all returned cups refunded and washed; excludes forfeitures, broken cups and prior deposit-rate changes.
Start with your inputs
Enter cups issued in period, cups returned in period, opening cups outstanding, deposit per cup (currency), wash capacity (cups/hour). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Cups issued in period | 100 |
| Cups returned in period | 80 |
| Opening cups outstanding | 20 |
| Deposit per cup (currency) | 3 |
| Wash capacity (cups/hour) | 40 |
A worked example
With the example inputs above, closing outstanding cups is 40. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Closing outstanding cups | 40 |
| Closing refundable deposits (currency) | 120 |
| Hours to wash returned cups | 2 |
How this is calculated
Closing outstanding cups
Roll forward opening cups with issue and return counts.
Closing refundable deposits (currency)
Apply the same deposit to all outstanding cups.
Hours to wash returned cups
Divide returned cups by measured wash throughput.
Symbols and units
- a
- Cups issued in period
- b
- Cups returned in period
- c
- Opening cups outstanding
- d
- Deposit per cup (currency)
- e
- Wash capacity (cups/hour)
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
Uniform deposit, all returned cups refunded and washed; excludes forfeitures, broken cups and prior deposit-rate changes.
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?
Closing outstanding cups; Closing refundable deposits (currency); Hours to wash returned cups. 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: Uniform deposit, all returned cups refunded and washed; excludes forfeitures, broken cups and prior deposit-rate changes.
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 →