Investment Calculator

This investment calculator projects how a portfolio grows over time when you combine an initial lump sum with regular monthly contributions and let compound returns do the work. It is the same engine behind a SIP (Systematic Investment Plan) projection, and it makes the single most important lesson in investing impossible to ignore: starting early and staying consistent matters far more than picking the "perfect" fund. It is built for anyone planning long-term wealth — a retirement corpus, a child's education, a house down-payment, or simply "how big can my SIP get?"

The compound-growth formula it uses

The calculator computes the future value (FV) as the sum of two parts — the growth of your initial amount, plus the growth of every monthly contribution:

FV = P × (1 + r)n + PMT × [((1 + r)n − 1) / r] × (1 + r)

Where:

• P = initial lump-sum investment
• PMT = monthly contribution (your SIP amount)
• r = monthly return = annual return ÷ 12 ÷ 100
• n = total months = years × 12

The trailing × (1 + r) is the annuity-due factor: it assumes each SIP instalment is invested at the start of the month, which is the standard convention used by Indian SIP, lumpsum and mutual-fund calculators. That keeps results consistent across the site so the same "₹X/month" input always agrees with the SIP calculator.

Worked example in ₹

Say you start with ₹1,00,000 and invest ₹10,000 every month at an assumed 12% annual return for 20 years. You contribute ₹1 lakh + (₹10,000 × 240) = ₹25 lakh of your own money over those two decades. Thanks to compounding, the projected corpus grows to roughly ₹1 crore — so well over ₹70 lakh is pure investment gain, not money you put in. Stretch the same SIP to 30 years instead of 20 and the corpus does not just grow by 50%; it multiplies several times over. That non-linear jump is the "magic of compounding", and the chart above makes the widening gap between "amount invested" and "portfolio value" visible year by year.

Choosing a realistic return rate (India)

The benchmark buttons above give sensible starting points. As long-run, indicative guidance — never a guarantee:

Equity returns are an average across decades, not a steady yearly figure — real markets swing widely in any single year. For conservative planning, model a lower rate (say 10% for equity) so you are pleasantly surprised rather than disappointed.

Tips & common mistakes

• Inflation eats nominal returns. A 12% nominal return with ~6% inflation is only about a 6% real return. When you set a future goal, remember that ₹1 crore will buy much less in 20 years than today.
• Step up your SIP. Increasing your monthly contribution by even 5%–10% a year (as your income rises) can dramatically outpace a flat SIP. This calculator models a fixed contribution — treat its result as a floor.
• Don't time the market. Rupee-cost averaging through a SIP buys more units when prices are low and fewer when high, smoothing out volatility. Stopping a SIP during a market dip is the most common — and most costly — mistake.
• Mind the tax on gains. Long-term capital gains on Indian equity and equity mutual funds (held over 12 months) are taxed at 12.5% above the annual exemption limit; short-term gains are taxed at 20%. Your post-tax corpus is what actually reaches your bank account.
• Past performance is not a promise. Historical averages guide assumptions but do not guarantee future results. Mutual fund investments are subject to market risks.