THE NUMBERS, EXPLAINED
How to use this calculator.
Pay required amounts first, then direct remaining budget to the highest rate. Released payments are rolled into the next debt. This is a simplified monthly model.
Start with your inputs
Enter balances (£), annual rates (%), minimum monthly payments (£), extra monthly budget (£). Keep amounts in the units shown on each field. The example is a starting point, not a recommended value.
| Input | Example value |
|---|---|
| Balances (£) | 1000,500 |
| Annual rates (%) | 10,20 |
| Minimum monthly payments (£) | 50,25 |
| Extra monthly budget (£) | 100 |
A worked example
With the example inputs above, months to debt free is 9. Change the inputs to explore your own scenario.
| Result | Example answer |
|---|---|
| Months to debt free | 9 |
| Interest (£) | 74.38 |
How this is calculated
Months to debt free
Keep monthly budget = sum(c)+d. Add each balance’s monthly interest at its annual percentage/1200, then pay its minimum capped at the amount owed. Apply remaining budget to the highest-rate outstanding debt first. Repeat until all balances are repaid, up to the 100-year horizon.
Interest (£)
Add all interest charged to all debts during the simulation.
Symbols and units
- a
- Balances (£)
- b
- Annual rates (%)
- c
- Minimum monthly payments (£)
- d
- Extra monthly budget (£)
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
sum(list) adds all entries in the list.
Assumptions and limits
Pay required amounts first, then direct remaining budget to the highest rate. Released payments are rolled into the next debt. This is a simplified monthly model.
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?
Months to debt free; Interest (£). 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: Pay required amounts first, then direct remaining budget to the highest rate. Released payments are rolled into the next debt. This is a simplified monthly model.
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.
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.
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