THE NUMBERS, EXPLAINED
How to use this calculator.
Input order is the supplied application priority; credit cannot be applied beyond an invoice balance. No tax or legal priority rule is inferred.
Start with your inputs
Enter open invoice balances in application order (currency), available credit note value (currency). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Open invoice balances in application order (currency) | 100,200,300 |
| Available credit note value (currency) | 250 |
A worked example
With the example inputs above, credit applied by invoice (currency) is 100, 150, 0. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Credit applied by invoice (currency) | 100, 150, 0 |
| Remaining invoice balances (currency) | 0, 50, 300 |
| Unused credit balance (currency) | 0 |
How this is calculated
Credit applied by invoice (currency)
Apply credit sequentially to invoices in supplied priority order.
Remaining invoice balances (currency)
Subtract credit applied to each invoice.
Unused credit balance (currency)
Return credit beyond all open balances.
Symbols and units
- a
- Open invoice balances in application order (currency)
- b
- Available credit note value (currency)
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
Input order is the supplied application priority; credit cannot be applied beyond an invoice balance. No tax or legal priority rule is inferred.
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?
Credit applied by invoice (currency); Remaining invoice balances (currency); Unused credit balance (currency). 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: Input order is the supplied application priority; credit cannot be applied beyond an invoice balance. No tax or legal priority rule is inferred.
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 →