Compound Interest Calculator

What is compound interest?

Compound interest is interest earned on both your original money and on the interest already added to it. Each time interest is credited, the base grows, so the next round of interest is bigger. In simple words, it is "interest on interest". Over short periods the effect is small, but over 10, 20 or 30 years it is the single biggest driver of wealth – and, on loans and credit cards, of debt.

What is a compound interest calculator?

A compound interest calculator shows how a sum of money grows at a fixed rate when interest is compounded. This free online tool lets you choose the compounding frequency – yearly, half-yearly, quarterly, monthly or daily – and add an optional monthly contribution, so it works for a one-time lumpsum, for a regular monthly investment, or both together. You get the maturity value, total invested, compound interest earned, the effective annual rate and a year-wise growth table in rupees or any currency.

How to use the compound interest calculator

Initial investment – the lumpsum you start with. Set it to 0 if you only invest monthly.
Interest rate – the yearly rate (nominal rate) offered or expected.
Time period – how many years the money stays invested.
Compounding frequency – how often interest is added. Bank FDs in India compound quarterly; many savings schemes compound yearly.
Monthly contribution – an amount you add at the end of every month, like an RD or SIP.

Compound interest formula

For a single deposit, the compound interest formula is:

A = P × (1 + r ÷ n)^{n × t}

Compound interest = A − P

A = maturity amount
P = principal
r = yearly interest rate as a decimal (10% = 0.10)
n = number of times interest is compounded per year (1, 2, 4, 12 or 365)
t = time in years

For regular monthly contributions made at the end of each month with monthly compounding, the future value of the contributions is C × ((1 + i)^m − 1) ÷ i, where C is the monthly amount, i = r ÷ 12 and m is the number of months. The calculator adds both parts together.

How to calculate compound interest with example

Yearly compounding

₹1,00,000 at 10% compounded yearly for 5 years: A = 1,00,000 × (1.10)⁵ = ₹1,61,051. Compound interest = ₹61,051. With simple interest you would earn only ₹50,000.

Monthly compounding

The same ₹1,00,000 at 10% compounded monthly for 5 years: A = 1,00,000 × (1 + 0.10 ÷ 12)⁶⁰ = ₹1,64,531. More frequent compounding adds ₹3,480 here.

With a monthly contribution

Start with ₹1,00,000, add ₹5,000 every month and earn 10% compounded monthly for 10 years. You invest ₹7,00,000 in total and end with about ₹12,94,929 – so ₹5,94,929 is compound interest. This is the default idea behind a SIP or a recurring deposit.

How compounding frequency changes the result

The table shows ₹1,00,000 at 10% for 10 years. The effective annual rate is the yearly rate that, compounded once a year, would give the same result.

Compounding	Maturity value	Effective annual rate
Yearly	₹2,59,374	10.000%
Half-yearly	₹2,65,330	10.250%
Quarterly	₹2,68,506	10.381%
Monthly	₹2,70,704	10.471%
Daily	₹2,71,791	10.516%

Moving from yearly to monthly compounding matters; moving from monthly to daily barely does. The rate and the time period matter far more.

How to calculate compound interest quarterly and half yearly

Divide the yearly rate by 4 (quarterly) or 2 (half-yearly) and multiply the years by the same number. For ₹1,00,000 at 8% for 3 years compounded quarterly: A = 1,00,000 × (1.02)¹² = ₹1,26,824. Half-yearly: A = 1,00,000 × (1.04)⁶ = ₹1,26,532.

The rule of 72

A quick mental shortcut: divide 72 by the yearly rate to estimate how many years it takes to double your money. At 8% money doubles in about 9 years; at 12% in about 6 years.

Compound interest in India: FD, RD, PPF and SIP

Fixed deposits – most banks compound FD interest quarterly. Use the FD calculator for bank-specific rules.
Recurring deposits – monthly deposits with quarterly compounding; see the RD calculator.
PPF, EPF, NSC – interest compounds yearly at government-set rates.
Mutual fund SIPs – returns are market-linked, not fixed, but the maths of compounding is the same. The SIP calculator uses expected returns.

Compound interest on loans

Compounding works against you on debt. Credit card balances in India can compound at 36–48% a year, so a ₹50,000 unpaid balance can grow very quickly. Home and personal loans charge interest monthly on the reducing balance, which is compounding by another name – but because EMIs repay part of the principal each month, the balance falls instead of growing.

Compound interest vs simple interest

Simple interest is paid only on the principal; compound interest is paid on principal plus accumulated interest. For savers compound interest is always better at the same rate. See the side-by-side comparison on the simple interest calculator.

Compound interest with inflation

A 10% return with 6% inflation grows your real purchasing power by only about 3.8% a year. To see what your maturity value will actually buy, run it through the inflation calculator.

Compound interest in Excel

Use =P*(1+r/n)^(n*t), for example =100000*(1+10%/12)^(12*5). With monthly contributions, use =FV(10%/12, 120, -5000, -100000), which returns about 12,94,929.

Monthly, quarterly, SIP or FD: what to enter

Monthly compounding and contributions – choose monthly compounding and add a monthly contribution, and the compound interest calculator shows how a regular monthly investment grows.
Daily compounding – choose daily for interest compounded on a daily basis, as some savings accounts do.
Quarterly or yearly – the quarterly formula is A = P × (1 + r/4)^4t; choose "yearly" and the compound interest calculator compounds annually.
Initial investment plus SIP – enter a lumpsum as the initial investment in the compound interest calculator, then add a monthly amount to model a lumpsum and SIP together. For a step up plan with compound interest, use the step-up SIP calculator.
SIP only – enter 0 as the initial amount and your monthly SIP to see it work like a SIP tool.
Rupees or dollars – amounts are in rupees by default, so the compound interest calculator suits India; switch the currency for USD.
Nothing to install – it runs free in your browser, so you need no app or spreadsheet.

Compound interest calculator yearly contribution

If you add money once a year, divide the yearly deposit by 12 and enter it in the compound interest calculator as a monthly contribution. The result is close – slightly higher, because money goes in earlier. A yearly investment of ₹60,000 becomes ₹5,000 a month.

Compound interest calculator for FD and RD

For an FD, choose quarterly compounding, as Indian banks do. How to calculate compound interest on FD: A = P × (1 + r/4)^4t. For an RD, enter the monthly deposit and choose quarterly compounding; the RD calculator follows bank rules more exactly.

A compound interest calculator for loan or compound interest calculator on loan shows how an unpaid debt grows: enter the balance and the loan rate with no contributions. For loans repaid by EMI, use the EMI calculator.

Compound interest calculator vs simple

The compound interest calculator vs simple comparison: at 10% for 5 years, ₹1 lakh earns ₹61,051 compounded yearly but ₹50,000 as simple interest. What is compound interest and simple interest? Compound interest adds interest to the principal; simple interest does not.

How to calculate compound interest for 3 years and half yearly

How to calculate compound interest for 3 years: ₹10,000 at 10% compounded yearly = 10,000 × 1.1³ = ₹13,310, so the interest is ₹3,310. How to calculate compound interest half yearly: use r/2 and 2t – ₹10,000 at 10% for 3 years = 10,000 × 1.05⁶ = ₹13,401. How to calculate compound interest rate from two values: r = (A ÷ P)^1/t − 1.

Compound interest calculator with inflation

For a compound interest calculator with inflation view, divide the maturity value by (1 + inflation)^years to get its value in today's money. What is compound interest in banking? It is how banks grow deposits – and loan balances – over time.

Compound interest calculator for India: SIP, PF and ULIP

Compound interest calculator for India SIP (monthly)

For a monthly SIP in India, set compounding to Monthly and enter the SIP as the monthly contribution with 0 as the principal. ₹5,000 a month at 12% for 10 years grows to about ₹11.5 lakh on ₹6 lakh invested. The SIP calculator gives a slightly higher figure because it assumes each SIP is invested at the start of the month.

Compound interest calculator yearly SIP

If you invest once a year, use yearly compounding: ₹60,000 invested at the start of each year for 10 years at 12% grows to about ₹11.79 lakh. Enter the first deposit as principal and model later years one by one, or use the yearly option in the SIP calculator.

Compound interest calculator for PF

EPF interest is compounded yearly at the rate the EPFO declares (8.25% for FY 2025-26). ₹1 lakh of PF balance left untouched for 10 years at 8.25% compounded yearly grows to about ₹2.21 lakh. For monthly contributions and the employer share, use the EPF calculator.

Compound interest calculator for ULIP

A ULIP compounds on the fund value after charges – premium allocation, mortality and fund management charges – so a ULIP fund growing at 10% gross may compound at only 8–9% net in the early years. Enter the net return, not the fund's headline return, when you use the compound interest calculator for a ULIP.

Compound interest calculator for days

The time field takes whole years, so for a period in days use the daily compounding formula A = P × (1 + r/365)^days. ₹1 lakh at 7% for 90 days compounded daily grows to about ₹1,01,741.

Compound interest calculator in Hindi

चक्रवृद्धि ब्याज (compound interest) में ब्याज पर भी ब्याज मिलता है। This compound interest calculator in Hindi terms: मूलधन (principal), ब्याज दर (interest rate), समय (time period) और चक्रवृद्धि आवृत्ति (compounding frequency) डालें; सूत्र है A = P(1 + r/n)^nt।

Compound interest calculator in XLS and for other currencies

In an XLS sheet, the compound interest calculator formula is =P*(1+r/n)^(n*t), e.g. =100000*(1+10%/12)^(12*10) returns ₹2,70,704. The maths is the same in any currency, so it works as a compound interest calculator for the USA (dollars), South Africa (ZAR) or Jamaica – just ignore the ₹ sign.

Best compound interest investments

The best compound interest investments reinvest their earnings automatically and let you stay invested for long periods. In India that includes PPF and EPF (tax-free, yearly compounding), cumulative FDs and RDs (quarterly compounding), and growth options of mutual funds via SIP. The longer the time and the higher the post-tax return, the more compounding does for you.

Frequently asked questions

What is the formula for compound interest?

A = P × (1 + r/n)^(n × t), where P is the principal, r the yearly rate as a decimal, n the compounding periods per year and t the years. Compound interest = A − P.

How much is ₹1 lakh at 10% compound interest for 5 years?

Compounded yearly it grows to ₹1,61,051. Compounded monthly it grows to about ₹1,64,531.

Is monthly compounding better than yearly?

Yes, at the same nominal rate. 10% compounded monthly equals an effective 10.47% a year, versus 10% for yearly compounding.

How do I calculate compound interest on an FD?

Most Indian bank FDs compound quarterly: A = P × (1 + r/4)^(4t). Choose "Quarterly" in the calculator.

Can I add monthly contributions?

Yes. Enter a monthly contribution and the calculator adds it at the end of each month and compounds it along with your initial amount.

What is compound interest in simple words?

It is interest on interest: the interest you earn is added to your money and then earns interest itself.

How long does it take to double money with compound interest?

Divide 72 by the yearly rate. At 9% money doubles in about 8 years.

How do I calculate compound interest for days?

Use A = P × (1 + r/365)^days for daily compounding. ₹1 lakh at 7% for 90 days grows to about ₹1,01,741.

Last updated 2026-09-18