How to use it
- 1.Enter the loan amount.
- 2.Enter the quoted annual rate.
- 3.Choose the tenure.
- 4.Compare the flat-rate total with the reducing-rate total and ask the lender which method applies.
Updated
Flat vs Reducing Rate Calculator
The flat vs reducing rate calculator takes one loan amount, rate and tenure and works out the monthly payment and total interest under both methods, so you can compare offers on total cost. Change every input and see the estimate update immediately.
Adjust your assumptions
₹
₹0₹5,00,00,000
%
024
years
130
Your estimate
₹11,875
Flat-rate monthly payment
Flat-rate interest
₹2,12,500
Reducing-balance EMI
₹10,258
Reducing-balance interest
₹1,15,496
Flat-rate total₹7,12,500
Reducing-rate total₹6,15,496
Educational estimate only. Methodology 2026.08. This is not a return promise, loan offer, tax filing or financial recommendation.
Results are estimates for learning and planning only. Tax rules, interest rates and scheme terms change from time to time, and your actual figures may differ. Please talk to a qualified financial advisor or chartered accountant before making any financial decision.
Flat vs Reducing Rate Calculator: what it calculates.
Some lenders quote a flat interest rate, which charges interest on the full original loan for the whole tenure. A reducing-balance rate charges interest only on what is still owed. The same headline rate therefore costs much more on a flat basis, and this calculator shows the difference in rupees.
The flat vs reducing rate calculator takes one loan amount, rate and tenure and works out the monthly payment and total interest under both methods, so you can compare offers on total cost.
How the calculation works.
Flat interest = P × r × t; Flat EMI = (P + Flat interest) ÷ (t × 12)
- P is the loan amount, r the annual rate and t the tenure in years.
- Reducing-balance EMI = P × i × (1 + i)^n / ((1 + i)^n − 1), where i = r ÷ 12 and n is the number of months.
- Under the flat method the interest does not fall as you repay.
- Compare total repayment, not just the quoted rate.
Worked example. A ₹5 lakh loan at 8.5% for 5 years costs ₹2,12,500 in interest on a flat basis, with a monthly payment of ₹11,875. On a reducing balance, the EMI is about ₹10,258 and interest is about ₹1,15,496, so the flat quote costs about ₹97,000 more.
What it helps with
- Exposes how much more a flat rate really costs.
- Shows both monthly payments side by side.
- Includes a reducing-balance repayment schedule.
What it does not include
- Fees, insurance and prepayment terms are excluded.
- Lenders may use other conventions or rounding.
- The result is an estimate; check the loan agreement for the actual method.
Common questions.
What is a Flat vs Reducing Rate Calculator?
It is an educational tool that applies the disclosed loan-rate comparison method to the assumptions you enter.
Are the results guaranteed?
No. Results are estimates, not forecasts, approvals, quotations or guarantees.
Why should I change the assumptions?
Testing conservative and optimistic inputs exposes uncertainty instead of hiding it behind one number.
Does it include tax and fees?
Only when a tax or fee is shown as an explicit input or result. Otherwise it is excluded.
How accurate is the calculator?
The mathematics follows the stated methodology, while real outcomes depend on rates, timing, rules, fees and circumstances.
Can I use this result as financial advice?
No. Use it for education and scenario comparison, then verify decisions with official documents or a qualified professional.
Why is inflation shown?
Inflation translates a future amount into approximate present-day purchasing power. The default 6% is editable and is not a forecast.
How often should I recalculate?
Recalculate when rates, income, contributions, rules, goals or repayment terms change.
Can the result differ from a bank or platform?
Yes. Institutions may use different compounding dates, rounding, charges and eligibility rules.
Is my data uploaded?
No. Calculations run locally in your browser and the input values are not sent to a calculation server.