How this calculation works
Work backwards from a goal to the fixed monthly contribution needed after allowing for investments you already hold. First decide whether the goal is priced in today’s money or is already the amount required at the future date. Applying inflation to an amount that is already a future target would count that price increase twice.
Worked example
This example uses illustrative inputs. Your current result is shown above.
Choose today’s-money target ₹1,00,000, 10% inflation, a 1-year horizon, ₹50,000 already invested and 0% return. The goal becomes ₹1,10,000, leaving ₹60,000 after existing savings. Twelve monthly deposits of ₹5,000 meet that modelled gap.
Assumptions and limits
- The fixed monthly SIP is invested at the beginning of each month.
- Existing investments and new contributions earn the same constant effective annual return.
- No withdrawals, tax, fees or annual contribution increases are modelled; an already funded goal produces a zero additional SIP.
Questions people ask
Which target-value basis should I choose?
Use today’s money for a cost quoted at current prices. Choose future money if you already have a required amount for the goal date; inflation is then not applied again.
Why does a larger current investment reduce the required SIP?
Its projected future value is deducted from the target before the new monthly payments are calculated. The same money should not also be counted as future contributions.
Does this guarantee I will reach the goal?
No. It solves a constant-return equation. A lower realised return, missed contributions or a higher final cost can leave a shortfall.