Lumpsum Calculator

Why this calculator matters

Windfall? Bonus? See what leaving it alone does vs spending it.

Numbers beat narratives. Move a single slider — return 8%→10%, years 20→25, monthly 5k→7k — and the left side answers instantly. That instant feedback is the whole product: you don’t need a spreadsheet, you need a feel for the trade-off.

Formula — the exact math we run

We compute

FV = P × (1 + r)^t • Real = FV / (1 + i)^t

Net = return − fee (if you entered a fee). Real = nominal / inflation. n = 12 for monthly, 4 for quarterly, 1 for yearly, 365 for daily. All money fields follow the currency you pick in the header.

Try this example — verify it yourself

▶ Copy these inputs

₹5L, 12%, 10y, 6% inflation → ₹15.5L nominal, ₹8.6L real, 3.1×. Add 5y → ₹27L.

Then change one thing — add 5 years, cut the fee from 1% to 0.1%, or raise inflation 3%→6% — and watch the real value move. That delta is the decision.

What each input actually does

Starting amount: one-time capital. Small but early beats large but late.
Monthly / yearly amount: the habit. For 20+ year horizons, this input drives >60% of the final number.
Return & inflation: nominal lies, real tells the truth. Use real = nominal − inflation for planning. Conservative real for India is 7–8% for equity, 2–3% for debt.
Years & compounding: years is the exponent. Frequency matters <1% vs monthly; fee matters 20–30%.
Advanced: frequency, inflation, fee. Fees look tiny (0.5%) but are charged on a growing balance — that’s why they snowball.

What the outputs mean

Final / corpus: what the account shows.
Invested: what you put in.
Gain / interest / earnings: the difference — the part that did no extra work.
Real (inflation-adjusted): what it buys today. Compare real across decades, not nominal.
Chart & table: hover the chart, audit the table. The gap between the two lines is your compounding; when it widens fast, you’re in the good part.

Assumptions — where it can be wrong

Constant return — markets aren’t. This is a median path.
No extra withdrawals, no missed contributions, on-time compounding.
Taxes/fees only if you entered them. For taxable, either lower the return or add the fee.
Currency symbols change formatting, not the amount — 5000 means 5000 in the selected currency.

Make it useful — 30-second tests

Slider test: move return 8→12→6 and years 15→25. Notice how 6% at 25y beats 12% at 15y — time > rate.
Fee test: set fee 0→1% and watch 30y corpus drop 25–30%. Then switch to a 0.1% fund.
Switch test: use the top “Switch” dropdown to hop to a related calculator without going home — compare lumpsum vs SIP for the same goal.
Share test: copy the URL after tuning — send it to a friend; they see your exact sliders and chart.

Common questions

Is this private? Yes. All math runs in your browser; we never see your numbers. The URL stores the inputs, not a server.

How close to reality? Formula-accurate, assumption-dependent. Use conservative real returns and round down for planning.

Can I see the steps? Yes — the yearly table shows Invested vs Balance row by row. The difference is earnings; its growth rate is the compounding.

Does changing currency convert? No — it only changes the symbol/formatting. 5000 means 5000 in that currency.

Can I export? Where you see Export CSV (SIP, PPF, etc.), it exports the exact schedule. Else copy the share URL.

When does a fee matter most? Always, but especially long horizons and large balances — that’s when the base for the fee is biggest.

When to use this vs the other calculators

Lumpsum vs SIP for same goal? Compare here.

Growth Curve

Invested vs Gain

Yearly breakdown