How it works
Runway is your savings divided by your monthly essential costs: how many months your savings would last if your income stopped and you spent only on essentials.
The projection runs month by month. Each month, the balance grows by the monthly equivalent of the annual real return, (1 + r)1/12 − 1, and then that month’s investment is added. If you set a yearly rise, the monthly amount increases by that percentage once a year.
Everything is in today’s rupees. The returns are real, after inflation, which is why your essential costs stay the same throughout. To read a result in future rupees you would add inflation back to both sides.
Why three returns. Nobody knows future returns, so we show a range. The defaults (2%, 4% and 6% a year after inflation) are illustrations spanning a cautious to a more hopeful long-run outcome for a mixed portfolio. They are not forecasts and are not based on any product. Change them to whatever you consider reasonable.
The cost of waiting repeats the middle projection with monthly investing starting later, and shows the difference in years of essential costs covered.
What this cannot tell you
- It ignores taxes, fees and the order in which good and bad years arrive.
- It assumes you keep investing every month and never withdraw.
- It cannot tell you what to invest in, how much risk suits you, or whether to repay a loan first.
- “Years covered” is a way to think about freedom, not a promise that savings would last that long.
Every result comes from the formulas above, run in your browser. There is no AI and no server involved, and the same inputs always give the same answer. Figures are educational estimates, not individualised financial advice.