THE NUMBERS, EXPLAINED
How to use this calculator.
Divide the remaining funding gap by the number of scheduled deposits before the deadline. No interest is assumed.
Start with your inputs
Enter target (£), already saved (£), remaining deposits. Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Target (£) | 1200 |
| Already saved (£) | 200 |
| Remaining deposits | 10 |
A worked example
With the example inputs above, deposit needed (£) is 100. Change the inputs to explore your own scenario.
Putting the example numbers into the formula
Deposit needed (£)
max(0,((1200)-(200)) ÷ (10)) = 100
| Result | Example answer |
|---|---|
| Deposit needed (£) | 100 |
How this is calculated
Deposit needed (£)
max(0,(a-b) ÷ c)
Symbols and units
- a
- Target (£)
- b
- Already saved (£)
- c
- Remaining deposits
Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.
Calculation steps and notation
max(x, y, …) selects the largest value.
Assumptions and limits
Divide the remaining funding gap by the number of scheduled deposits before the deadline. No interest is assumed.
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?
Deposit needed (£). 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: Divide the remaining funding gap by the number of scheduled deposits before the deadline. No interest is assumed.
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
Investor.gov: financial planning tools ↗
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 →