Question 1

What is an investment calculator?

Accepted Answer

An investment calculator projects the future value of your money based on an initial lump sum, regular periodic contributions, annual return rate, compounding frequency, and investment duration. It uses compound interest mathematics to show how wealth grows exponentially over time — illustrating why starting early and staying consistent produces dramatically better results than investing larger amounts later. It is ideal for planning SIPs, mutual fund goals, stock portfolios, retirement savings, and education funds.

Question 2

What is compound interest and why does it matter?

Accepted Answer

Compound interest means earning returns not just on your original investment but also on all previously earned returns. A Rs 1 lakh investment at 12% annual return: after 10 years = Rs 3.1 lakh; after 20 years = Rs 9.6 lakh; after 30 years = Rs 29.9 lakh. The growth accelerates because each year's gains are added to the base for the next year's calculation. This exponential effect is why Warren Buffett calls compound interest the eighth wonder of the world and why time in the market is more powerful than timing the market.

Question 3

Can I use this for SIP or mutual fund planning?

Accepted Answer

Yes. For a Systematic Investment Plan (SIP), set your initial investment to zero (or your existing corpus), enter your monthly SIP amount as the recurring contribution, set frequency to monthly, and enter your expected CAGR as the annual return rate. The calculator will project the future value of your SIP. For example, Rs 5,000/month at 12% annual return for 20 years grows to approximately Rs 49.9 lakh — on total contributions of only Rs 12 lakh. The extra Rs 37.9 lakh is pure compound growth.

Question 4

How does compounding frequency affect returns?

Accepted Answer

More frequent compounding generates slightly higher returns on the same nominal annual rate. On Rs 1 lakh at 10% annual rate for 10 years: annual compounding = Rs 2,59,374; quarterly compounding = Rs 2,68,506; monthly compounding = Rs 2,70,704; daily compounding = Rs 2,71,791. The difference between annual and monthly compounding is about 4.4% over 10 years. For long investment horizons, monthly compounding (the default for most mutual funds and SIPs) is the most realistic assumption.

Question 5

What annual return rate should I use?

Accepted Answer

Historically, these are reasonable long-term nominal return assumptions: Large-cap equity funds / S&P 500 index — 10-12% CAGR; Diversified equity mutual funds (India) — 12-15% CAGR in good periods, 10-12% conservatively; Balanced / hybrid funds — 8-10%; Debt mutual funds / bonds — 6-8%; Fixed deposits / savings accounts — 5-7%. For planning purposes, using 10-12% for equity-heavy portfolios and 7-8% for balanced portfolios is standard. Always use a conservative estimate — it is better to save more and have surplus than to save less and fall short.

Question 6

What is CAGR and how is it different from absolute return?

Accepted Answer

CAGR (Compound Annual Growth Rate) is the annualized rate at which an investment grows over a multi-year period, accounting for compounding. Absolute return is simply the total percentage gain regardless of time. For example, doubling your money (100% absolute return) in 5 years = 14.87% CAGR; in 10 years = 7.18% CAGR. CAGR is the standard measure for comparing investments of different durations. Mutual fund performance ratings and this calculator both use CAGR as the return metric.

Question 7

How do taxes and inflation affect investment returns?

Accepted Answer

This calculator shows nominal (pre-tax, pre-inflation) growth. To account for taxes: subtract your expected tax rate on gains from the return rate (e.g., if equity gains are taxed at 10% LTCG and your gross return is 12%, use 10.8% net). To account for inflation: subtract the inflation rate from the nominal return to get the real return (12% nominal return minus 6% inflation = approximately 6% real return). For a complete picture of purchasing power, enter your after-tax, after-inflation return rate as the annual return.

Question 8

What is the Rule of 72?

Accepted Answer

The Rule of 72 is a quick mental math shortcut to estimate how long it takes to double your money at a given return rate: Years to double = 72 / annual return rate. At 6% return, money doubles in 12 years. At 9% return, it doubles in 8 years. At 12% return, it doubles in 6 years. This rule helps quickly compare investments — a fund returning 12% will double your money twice as fast as one returning 6%. It is an approximation that works well for rates between 6-12%.

Question 9

Should I invest a lump sum or in regular installments?

Accepted Answer

Both strategies have advantages. Lump sum investing is better mathematically when markets are trending upward — your full amount is compounding from day one. Regular installments (SIP/DCA — Dollar Cost Averaging) reduce timing risk by buying more units when prices are low and fewer when prices are high, averaging your cost over time. Studies show that in volatile markets, DCA often outperforms lump sum investing for individual investors because it removes the temptation to time the market. This calculator supports both approaches — set recurring contribution to zero for lump sum.

Question 10

Are my investment details private?

Accepted Answer

Yes, completely. All investment calculations run entirely within your browser using JavaScript. No initial amount, contribution, return rate, or personal data is transmitted to any server, stored in a database, or shared with any third party. The calculator works fully offline once the page loads. You can safely model your actual financial figures without any privacy concerns.

Investment Calculator

Investment Formula

Example Calculation

Related Tools & Guides

Frequently Asked Investment Questions

How to Use This Calculator

Step 1: Choose your currency

Step 2: Enter initial investment

Step 3: Set recurring contributions

Step 4: Select duration & annual rate

Step 5: Choose compounding frequency

Step 6: Hit Calculate or use example for demo!