Investments • Annual compounding
Lumpsum Calculator
Estimate how a one-time investment may grow under a constant illustrative annual return. Use several scenarios because market returns are not smooth or guaranteed.
Enter investment assumptions
An assumption, not a promised return.
How to use it
- Enter the one-time amount.
- Add a cautious expected annual return.
- Enter the duration.
- Calculate invested amount, estimated gain and maturity.
- Repeat with lower and higher assumptions.
This calculator is useful for comparing scenarios for an existing corpus, bonus or planned one-time investment. It is not a product recommendation.
Formula and methodology
A = P × (1 + r)t
P is initial principal, r is annual return as a decimal, and t is years. Wealth gained equals A minus P. Display values are rounded to the nearest rupee.
The formula assumes annual compounding and one unchanged rate. It excludes contributions after day one.
Worked example
An illustrative investment of ₹5,00,000 for 10 years at 12% annual compounding gives:
| Amount invested | ₹5,00,000 |
|---|---|
| Estimated wealth gained | ₹10,52,924 |
| Estimated maturity value | ₹15,52,924 |
The 12% rate is not a forecast. Actual market returns can be uneven or negative.
How to interpret the result
The maturity value is the mathematical future value under the entered assumption. The gain is not guaranteed interest. A smooth projection hides volatility and sequence risk.
Common mistakes
- Using a past high return as a future promise.
- Ignoring tax, fees and inflation.
- Investing emergency money in a volatile product.
- Choosing a product only from projected maturity.
Practical tips
- Test a lower-return scenario first.
- Keep short-term needs separate.
- Understand the underlying product and risk.
- Compare future value with inflation.
- Review allocation instead of reacting to daily movement.
Related calculators and guides
Frequently asked questions
What is a lumpsum investment?
A one-time investment rather than monthly contributions.
Is the return guaranteed?
No.
What compounding is used?
Annual compounding.
Are tax and costs included?
No.
Can I compare several assumptions?
Yes, and that is recommended.
Is lumpsum better than SIP?
Not universally; circumstances and risk differ.
Can a real investment lose value?
Yes. This smooth positive-return model cannot show market losses.
Is this each year's actual return?
No. It is one constant planning assumption.
Educational disclaimer
This calculator is for general education, not personalised investment advice. Market-linked returns are not guaranteed and actual values can be lower than the amount invested.