A SIP calculator is a familiar tool on mutual fund websites and an easy one to misread. It does not predict anything. It does arithmetic on numbers you supply. Used properly it is a good way to see how amount, time and rate interact. Used carelessly it produces a large figure that people mistake for a promise.
This guide describes the SIP calculator on this website as it works on 11 October 2026.
Key points
- You enter three things: a monthly amount, an assumed annual return and a period in years.
- The result is an illustration at a constant rate. Real returns are never constant and can be negative.
- The assumed rate starts as a placeholder and is yours to change. It is not a forecast, and it is not the return of any scheme, category or index.
- Time has more effect on the result than most people expect, which is the main lesson of the tool.
- Run at least two rates, one cautious, before drawing any conclusion.
The three inputs
| Input | What it means | Range in our calculator |
|---|---|---|
| Monthly investment | The fixed amount invested each month | ₹500 to ₹2,00,000 |
| Assumed annual return (%) | A constant yearly rate used for the arithmetic. It opens at a placeholder figure that you can change | 1% to 20% |
| Investment period | How many years the SIP runs | 1 to 40 years |
You can type a value or move the slider. The figures update as you change them.
The calculator opens with example values already filled in. On the day this guide was written they were ₹10,000 a month, 8% a year and 10 years, which gives an illustrative final value of about ₹18.42 lakh on ₹12.00 lakh invested. Those are placeholders so that an example can be shown. The 8% is not a forecast, not an indication of likely returns and not the return of any scheme. The note under the field says the same. Change the rate to your own assumption before you read anything into the result.
The three results
- Total invested: the monthly amount multiplied by the number of months.
- Illustrative final value: what the instalments would add up to if every month earned exactly the assumed rate.
- Illustrative gain: the difference between the two.
Below the tiles you will find a chart of invested amount against illustrative value year by year, and a year-wise table.
How the figure is worked out
The calculator uses the standard future-value formula for a regular investment, with each instalment made at the start of the month:
Final value = P × [((1 + i)^n − 1) ÷ i] × (1 + i)
where P is the monthly amount, i is the annual rate divided by 12, and n is the number of months.
It assumes every instalment is paid on time, the amount never changes and the rate is the same every month. None of these holds in real life.
A worked illustration
Take ₹10,000 a month. The table shows the calculator’s output at three assumed rates. These are hypothetical figures for arithmetic, not forecasts and not the performance of any scheme.
| Period | Total invested | At 8% | At 10% | At 12% |
|---|---|---|---|---|
| 10 years | ₹12.00 lakh | ₹18.42 lakh | ₹20.66 lakh | ₹23.23 lakh |
| 20 years | ₹24.00 lakh | ₹59.29 lakh | ₹76.57 lakh | ₹99.91 lakh |
Two things stand out.
Time. Doubling the period from 10 to 20 years doubles the amount invested but more than triples the illustrated value at each rate. Growth on earlier growth is what does this, and it needs years to show.
The rate assumption. Over 20 years the difference between assuming 8% and assuming 12% is about ₹40 lakh on the same instalments. A plan that only works at the higher figure is a fragile plan.
Choosing a rate to assume
Nobody knows what future returns will be. Some guidance on choosing a figure for illustration:
- Match the rate to what the money would be invested in. An assumption that might be argued for a long-term equity allocation is not appropriate for a goal three years away that should be in steadier categories.
- Run a cautious case first. If the goal is met at a modest rate, a better outcome is a bonus.
- Do not raise the rate to make the required SIP affordable. A plan built that way can fall short.
- Remember costs and tax. The calculator ignores scheme expenses, exit load and tax.
- Think in today’s rupees. A large figure twenty years away will buy much less than it would today. Use the inflation calculator alongside.
Useful ways to use it
- Compare starting now with starting later. Run the same amount for 20 years and for 15. The gap is the cost of waiting five years, at your assumed rate.
- Test a higher amount. See what an extra ₹2,000 a month does over the full period.
- Work backwards from a goal. If you know the target, the goal planner solves for the monthly amount directly and adjusts for inflation.
- Check a rising SIP. If you expect to increase your instalment each year, use the step-up calculator instead. Step-up SIP explained describes how the facility works.
What the calculator cannot tell you
- The path. A real investment does not rise in a smooth line. Along the way its value will fall below the amount invested at times, possibly for long stretches.
- The ending. The value in the final years depends heavily on what markets do then. A fall near the end affects the whole accumulated amount.
- Which scheme. The tool knows nothing about schemes, categories or risk.
- Whether a SIP suits you. That depends on your goals, your horizon, your emergency fund and how you would react to a decline.
After the calculator
A figure from the calculator is the start of a conversation, not the conclusion. The next questions are what the money is for, when it is needed and how much risk the goal can bear. Our pages on goal-based investing and on market risk take those up. For retirement, see how to use the retirement planner.
Risk note
Every figure produced by the calculator is illustrative and based on an assumed rate. Mutual fund returns are not guaranteed and can be negative.
Frequently asked questions
What rate of return should I enter?
There is no correct figure. Enter a cautious rate and a more optimistic one, and plan around the cautious case.
Does the result include tax and charges?
No. Tax and exit load are ignored. The assumed rate is applied as given.
Why is my actual SIP value different from the calculator?
Because real returns vary month to month, instalments are allotted at different NAVs, and costs and timing differ from the simple assumptions in the formula.
Is my data stored when I use the calculator?
The calculators run in your browser. The figures you enter are sent to our server only when you press Download PDF Report, to create the file. They are not stored.