Interest Rate Calculator
Use this free interest rate calculator to see exactly how much a loan or investment will cost you, before you commit to anything. Enter your principal, rate, and tenure to get your total interest and full repayment amount in seconds. Then download your free report and keep the numbers handy.
Interest Rate Calculator
Understand the true cost of your loan by comparing interest types
Loan Parameters
Comparison Summary
Flat Rate EMI
0
Higher Total Cost
Reducing Rate EMI
0
Lower Total Cost
Total Interest Saved with Reducing Rate
0
How to Use This Interest Rate Calculator
Let’s go over the details. Five fields. Each one changes your result.
Principal Amount: The original amount you’re borrowing or investing. Enter 5,00,000 for a ₹5 lakh loan or 10,000 for a $10,000 personal loan.
Interest Rate (% per annum): The annual rate your lender quoted. Enter it as a number, not a decimal. If your bank said 11.5%, type 11.5.
Time Period: Enter in years. A 3-year loan goes in as 3. If your tenure is in months, divide by 12.
Interest Type: Choose Simple or Compound. Most personal loans and car loans in India use reducing balance (a form of compound). Fixed deposits use simple interest. If you’re not sure, check your loan agreement.
Compounding Frequency (for compound interest): Monthly, quarterly, or annually. The more frequent the compounding, the more interest you actually pay. Most Indian home loans compound monthly.
Hit Calculate. Your results show up instantly: total interest, total amount payable, and a year-by-year breakdown.
Then hit Download Report. You get a clean PDF with all your inputs and outputs in one place. No login needed. No cost. It’s yours to keep, print, or share. None of our competitors give you this. You’re comparing lenders? Run the numbers for each one and download a separate report for each. Side by side, it gets very clear, very fast.
Real Example: India
A borrower in Hyderabad takes a personal loan of ₹3,00,000 at 13% per annum, compounded monthly, for 3 years.
Now change the tenure to 5 years, same principal and rate.
The EMI looks more affordable. And you pay ₹47,122 more in total. That trade-off is what the interest rate calculator shows you before you sign anything.
Real Example: US
A $15,000 car loan at 7.5% annual interest, compounded monthly, over 4 years.
Extend to 6 years: monthly payment drops to $258 but total interest rises to $3,584. You pay $1,143 extra to lower your monthly bill by $105.
After the $380 existing obligation, the maximum new mortgage payment is roughly $2,200/month — which corresponds to an eligible loan of approximately $330,000.
Simple Interest vs Compound Interest: Which One Are You Paying?
Most people don’t check. They should.
Simple Interest Formula:
SI = P × R × T / 100
Where P is principal, R is rate per annum, T is time in years.
Compound Interest Formula:
Where n is the number of compounding periods per year.
On a ₹5,00,000 loan at 10% for 3 years:
| Interest Type | Total Interest | Total Amount |
|---|---|---|
| Simple Interest | ₹1,50,000 | ₹6,50,000 |
| Compound (Annual) | ₹1,65,500 | ₹6,65,500 |
| Compound (Monthly) | ₹1,61,617 | ₹6,61,617 |
The difference between simple and monthly compounding on this loan is ₹11,617. That’s not nothing. And most lenders don’t explain it upfront.
What Nobody Tells You About the Rate You’re Entering
Here’s the thing: the rate your lender gives you isn’t always the rate you’re actually paying.
The nominal interest rate is the headline number. What you see in the brochure.
The Effective Annual Rate (EAR) is the real cost after compounding is applied. Under RBI’s Fair Practices Code circular (2023 update), lenders are required to disclose the annualised rate, but many still lead with the nominal figure in their marketing.
A 12% nominal rate compounded monthly has an EAR of 12.68%. On a ₹10 lakh loan over 5 years, that 0.68% difference adds up to over ₹18,000 in extra interest.
When you use this interest rate calculator, you’re seeing the actual math, not the marketing number.
And if you want to take that calculation to a lender negotiation, download the report. Having your numbers on paper changes the conversation.
Interest Rate Comparison: What Indian Lenders Are Charging (2025)
| Lender | Loan Type | Interest Rate | Compounding |
|---|---|---|---|
| SBI | Personal Loan | 11.45% – 14.60% | Monthly |
| HDFC Bank | Personal Loan | 10.75% – 21.30% | Monthly |
| Bajaj Finance | Personal Loan | 11% – 35% | Monthly |
| Shriram Finance | Vehicle Loan | 11.5% – 18% | Monthly |
| Post Office FD | Fixed Deposit | 6.9% – 7.5% | Quarterly |
| SBI FD | Fixed Deposit | 6.5% – 7.1% | Quarterly |
Run any of these rates through the calculator. Download the result. Compare them side by side. The difference between 11.45% and 14.60% on a ₹5 lakh personal loan over 3 years is roughly ₹24,000 in total interest.
4 Mistakes People Make With an Interest Rate Calculator
- Entering the flat rate instead of the reducing balance rate. Many vehicle loan and personal loan brochures advertise a flat rate. A flat rate of 8% equals roughly 14.5–15% on a reducing balance basis. If you enter the flat rate into this calculator, your total interest will look much lower than what you’ll actually pay.
- Ignoring compounding frequency. Changing from annual to monthly compounding on the same rate increases your effective interest cost. Most borrowers enter 12% and assume compounding doesn’t matter. It does.
- Using the calculator for investments and confusing it with loan math. An FD at 7.5% compounded quarterly and a personal loan at 7.5% compounded monthly are not the same cost. One earns you money. The other costs you more than the number suggests.
- Not downloading the report before the rate changes. Floating rate loans tied to MCLR or the repo rate can change. Run the calculator at today’s rate, download the report, and you have a baseline. When rates move, you can re-run and see exactly what changed.
FAQ on Interest Rate Calculator
Disclaimer: This interest rate calculator provides estimates based on the inputs you enter and standard interest calculation methods. Results are for reference only and do not represent a formal loan offer, investment advice, or guaranteed return. Actual interest amounts may vary based on your lender’s terms, processing fees, and applicable taxes. Always confirm final figures directly with your bank or financial institution before making any decision.
