THE NUMBERS, EXPLAINED
How to use this calculator.
Allocate capacity in proportion to stated requirements when oversubscribed; otherwise allocate each member exactly their requirement. No account limits or provider rules are inferred.
Start with your inputs
Enter required storage by family member (gb), shared plan capacity (gb). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Required storage by family member (GB) | 20,30,50 |
| Shared plan capacity (GB) | 80 |
A worked example
With the example inputs above, allocated storage by member (gb) is 16, 24, 40. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Allocated storage by member (GB) | 16, 24, 40 |
| Unmet storage (GB) | 20 |
| Unused plan capacity (GB) | 0 |
How this is calculated
Allocated storage by member (GB)
Scale every requirement by capacity divided by total demand, capped at one.
Unmet storage (GB)
Subtract shared capacity from demand, floored at zero.
Unused plan capacity (GB)
Subtract demand from capacity, floored at zero.
Symbols and units
- a
- Required storage by family member (GB)
- b
- Shared plan capacity (GB)
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
Allocate capacity in proportion to stated requirements when oversubscribed; otherwise allocate each member exactly their requirement. No account limits or provider rules are 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?
Allocated storage by member (GB); Unmet storage (GB); Unused plan capacity (GB). 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: Allocate capacity in proportion to stated requirements when oversubscribed; otherwise allocate each member exactly their requirement. No account limits or provider rules are 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 Prealgebra 2e — arithmetic and proportions ↗
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 →