This monthly compound interest calculator shows what a sum grows to when interest is credited to it every month, so each month's interest earns interest from the next month on. Fill in principal, annual rate and duration. Out come the final value, the true yearly yield and a quarterly comparison, since quarterly is the norm for Indian bank deposits.
Monthly compounding shows up in some deposits and NBFC schemes, in many loan and card calculations, and in school and college maths problems.
At a glance
- FormulaA = P × (1 + r/12)^(12 × t)
- ₹1 lakh at 12% for 1 year₹1,12,683
- Effective rate12.68% from 12% quoted
- Quarterly instead₹1,12,551
- Monthly rateYearly rate ÷ 12
- Months in the formulaYears × 12
How the monthly compound interest calculator works
The yearly rate is split into 12 monthly rates. Each month, interest at that rate is worked out on the current balance and added to it. After t years there have been 12 × t such steps:
A = P × (1 + r/12)^(12 × t)
Put ₹1 lakh in for a year at 12%: each month adds 1%, 1.01^12 is 1.12683, and the balance ends at ₹1,12,683. That is ₹683 more than simple interest and ₹132 more than quarterly compounding. The effective yearly rate, 12.68%, is the number to compare with other products.
Compound interest calculator monthly vs quarterly vs yearly
| ₹2,00,000 at 9% for 5 years | Maturity value | Interest |
|---|---|---|
| Yearly | about ₹3,07,725 | about ₹1,07,725 |
| Quarterly | ₹3,12,102 | ₹1,12,102 |
| Monthly | ₹3,13,136 | ₹1,13,136 |
| Simple | ₹2,90,000 | ₹90,000 |
Monthly beats quarterly by about ₹1,000 here. Useful, but small next to the difference a better rate or a longer period makes. The daily compound interest calculator goes one step further.
Monthly compounding in loans
Loan EMIs use a monthly rate too: interest each month is the yearly rate ÷ 12 on the balance. Because you pay that interest every month through the EMI, it does not pile up. If you miss EMIs, though, overdue interest and charges can be added to what you owe, and then it compounds against you. Credit card balances work on similar or shorter cycles. See the EMI calculator and the credit card EMI calculator for those cases.
Monthly compound interest calculator India: deposits that use it
Most bank FDs compound quarterly, but some deposit schemes, especially from NBFCs and housing finance companies, offer monthly compounding on cumulative deposits. When comparing two deposits:
- Convert each to an effective yearly rate.
- Check safety: bank deposits have DICGC cover up to ₹5 lakh; company deposits do not, and depend on the company's credit rating.
- Check tax: interest is taxable either way.
For bank deposits, the FD calculator uses quarterly compounding by default. Every frequency can be tried on the home page tool.
Doing it by hand
To compound monthly without a calculator, divide the yearly rate by 12 and multiply the balance by (1 + that rate) once for every month. For 6 months at 9% on ₹50,000: monthly rate 0.75%, so ₹50,000 × 1.0075^6 = ₹52,292. A phone calculator with a power key makes this quick: 1.0075, raise to 6, times 50,000. In a spreadsheet, use =P*(1+r/12)^(months).
Where you will see monthly compounding
- Cumulative deposits from some housing finance companies and NBFCs.
- Recurring savings plans that credit interest monthly.
- Textbook and exam problems on compound interest.
- Debt: overdue loan interest and card balances, where the effect works against you.
Whenever a product says interest is credited monthly, use this tool; when it says quarterly, switch to the quarterly option on the main page.
Frequently asked questions
What is the formula for monthly compound interest?
Multiply P by (1 + r/12) raised to 12 × t, with r as a decimal and t in years; take P away to get the interest alone.
What is 12% compounded monthly as a yearly rate?
12.68% effective. ₹1 lakh grows to ₹1,12,683 in one year.
Is monthly compounding better than quarterly?
Slightly, for a depositor. For ₹2 lakh over 5 years at 9%, roughly ₹1,000 separates them.
Do Indian banks compound FDs monthly?
Usually quarterly. Some company deposits and special schemes compound monthly. Check the deposit terms.
How do I calculate monthly compound interest for months, not years?
Use the number of months directly as the power: P × (1 + r/12)^months. In the calculator, type months ÷ 12 as years.
Is this tool set up for Indian users?
Yes. It works in rupees and follows the standard formula used by Indian banks and textbooks.