THE NUMBERS, EXPLAINED
How to use this calculator.
Expiry happens before the listed bookings; oldest eligible credits are used first, with no cash value attached to unused credit.
Start with your inputs
Enter opening meeting credits, new period meeting credits, credits expiring before bookings, booking charges in credits, maximum credits allowed to roll forward, cash price per excess credit (currency). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Opening meeting credits | 10 |
| New period meeting credits | 20 |
| Credits expiring before bookings | 5 |
| Booking charges in credits | 30 |
| Maximum credits allowed to roll forward | 10 |
| Cash price per excess credit (currency) | 5 |
A worked example
With the example inputs above, credits available after expiry is 25. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Credits available after expiry | 25 |
| Excess booking credits | 5 |
| Overage invoice (currency) | 25 |
| Credits rolled forward | 0 |
How this is calculated
Credits available after expiry
Add new credits and deduct known expiry before use.
Excess booking credits
Compare bookings with available credits.
Overage invoice (currency)
Price only booking credits beyond allowance.
Credits rolled forward
Cap unused credit carryover under the supplied rule.
Symbols and units
- a
- Opening meeting credits
- b
- New period meeting credits
- c
- Credits expiring before bookings
- d
- Booking charges in credits
- e
- Maximum credits allowed to roll forward
- f
- Cash price per excess credit (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
Expiry happens before the listed bookings; oldest eligible credits are used first, with no cash value attached to unused credit.
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?
Credits available after expiry; Excess booking credits; Overage invoice (currency); Credits rolled forward. 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: Expiry happens before the listed bookings; oldest eligible credits are used first, with no cash value attached to unused credit.
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 →