Compound interest calculator.
See what your savings could become. Start with your numbers, then explore the possibilities.
Your investment
Fine-tune your calculation
Annual rate is nominal. Currency changes formatting only. Returns are assumed constant; taxes and fees are excluded.
Projected value in 20 years
₹34,37,782Small steps today. A clearer picture of tomorrow.Your growth journey
Under these assumptions, growth adds ₹21,37,782 beyond your contributions. The effective annual rate is 8.30%.
Estimates, not guaranteed returns. Market investments can rise or fall. Amounts are rounded for display.
Understand what makes it grow.
Time, contributions and your assumed rate each tell a different part of the story. Change one at a time to see its effect.
Growth that earns
growth of its own.
Compound interest means earning interest on your original money and on interest already accumulated. Over longer periods, that second layer can become a meaningful part of the balance.
For example, 10,000 growing at 8% a year earns 800 in year one. If it stays invested, the next year’s 8% applies to 10,800, adding 864.
Explore the worked example- A
- Projected ending balance
- P
- Starting amount
- r
- Nominal annual rate as a decimal
- n
- Compounding periods per year
- t
- Time in years
How this calculator handles regular contributions
For d contributions per year, the equivalent period rate is i = (1 + r/n)n/d − 1. For end-of-period contributions, each period becomes B = B × (1 + i) + C. For start-of-period contributions, B = (B + C) × (1 + i).
An annual increase applies to the contribution from year two onward. Inflation-adjusted value is A ÷ (1 + inflation)t. Goal mode solves for the initial regular contribution using the same schedule and annual increases. The target is a future nominal amount.
We keep full precision during calculation and round only the displayed results. This model excludes taxes, fees, irregular cash flows and product-specific crediting rules. It uses whole-year durations of 1–60 years.
Good questions. Useful answers.
What actually happens when interest compounds?
Follow the numbers from the first year to the tenth.
THE DETAILS · 4 MIN READMonthly or yearly: how much does it matter?
Separate compounding frequency from contribution frequency.
THE HABIT · 4 MIN READWhat changes when you add a little, regularly?
See how timing and annual increases affect your projection.
A few things
worth understanding.
How is compound interest different from simple interest?+
Simple interest is calculated on the original principal. Compound interest also earns a return on accumulated interest. With no new deposits, 10,000 at 8% compounded annually becomes 11,664 after two years, compared with 11,600 using simple interest.
Can I add money monthly but compound annually?+
Yes. Contribution frequency and compounding frequency are independent here. We convert the nominal annual rate into an equivalent contribution-period rate. For deposits between compounding dates, we use fractional-period exponential growth. Actual bank crediting and day-count rules may differ.
Is this a mutual fund or SIP calculator?+
This is a constant-rate compound growth model. It can illustrate regular investing, but it does not simulate a particular fund, changing NAV, charges, taxes or market volatility. A nominal rate compounded monthly is also different from an annualized fund-return assumption.
What does the inflation setting change?+
It adds the projected ending balance expressed in today’s purchasing power. It does not change the nominal balance, increase your contributions or automatically adjust your goal.
Are my calculations saved or uploaded?+
Calculations happen in your browser. We do not send your financial inputs to an API or save them in browser storage. A comparison lasts only while this page remains open. CSV and print exports are actions you choose.
Can I use a negative rate?+
Yes, annual nominal rates from −50% to 50% are supported, so you can explore loss scenarios. A constant rate is an illustration, not a forecast.