What is EMI?
EMI — Equated Monthly Installment — is the fixed amount you pay every month against a loan until it's fully repaid. Same number, every month, for the full tenure. What changes silently each month is the split between interest and principal: early on, almost all of it is interest; near the end, almost all of it is principal.
If you've ever signed a loan paper and wondered what the monthly damage will be on your salary, the EMI calculator is the first thing to run before you sign.
How is EMI calculated?
The reducing-balance EMI formula — used by every Indian bank, NBFC, and most global lenders:
EMI = P × r × (1 + r)^n / ((1 + r)^n − 1)
where:
P= principal (loan amount in ₹)r= monthly interest rate = annual rate / 12 / 100n= total number of months = tenure × 12EMI= the fixed monthly payment
CalcMaster also generates the full amortization schedule — month-by-month showing how much of each EMI goes to interest vs principal, and the remaining balance.
Worked example
A typical Indian home loan: ₹50 lakh, 9% annual rate, 20-year tenure.
| Step | Value |
|---|---|
Principal P |
₹50,00,000 |
Monthly rate r |
0.0075 (9% / 12 / 100) |
Number of months n |
240 |
(1 + r)^n |
6.0092 |
| Monthly EMI | ₹44,986 |
| Total paid over 20 years | ₹1,07,96,711 |
| Total interest | ₹57,96,711 |
You borrowed ₹50 lakh. You'll pay back ₹1.08 crore. The bank's profit — the interest — is more than the principal itself. This is why long-tenure loans are quietly expensive even at moderate rates.
Components and inputs explained
Loan amount (principal)
What you're actually borrowing — not the property/car price. Subtract your down payment, trade-in, and any subsidy from the asking price.
Interest rate
The bank's annual rate. Note: banks quote either flat rate or reducing-balance — they look similar but flat rate is roughly double the effective cost. Always confirm "reducing balance" before signing.
Current Indian benchmarks (mid-2025):
- Home loan: 8.4–9.5%
- Car loan: 9–11%
- Personal loan: 11–18%
- Credit card EMI (most expensive): 24–36%
Tenure
The repayment period. Longer tenure = lower EMI but much higher total interest. See the comparison below.
Tenure tradeoff: 20-yr vs 30-yr on ₹50L at 9%
| Tenure | EMI | Total interest | Total paid |
|---|---|---|---|
| 15 years | ₹50,713 | ₹41.3 L | ₹91.3 L |
| 20 years | ₹44,986 | ₹58.0 L | ₹1.08 cr |
| 25 years | ₹41,961 | ₹75.9 L | ₹1.26 cr |
| 30 years | ₹40,232 | ₹94.8 L | ₹1.45 cr |
The 30-year tenure saves you ₹4,754/month on the EMI but costs you ₹37 lakh more in total interest. If you can afford the shorter tenure, take it.
Common types
| Type | What's different | Where you see it |
|---|---|---|
| Reducing balance (default) | Interest on remaining balance | All Indian bank loans, mortgages |
| Flat rate | Interest on original principal for full tenure | Some money-lenders, BNPL schemes. Effective rate is ~2× the quoted rate. Avoid. |
| Bullet payment | Interest-only EMI; principal at the end | Bridge loans, some commercial loans |
| Balloon payment | Lower EMIs, one large payment at the end | Auto leases, some commercial financing |
Prepayment: the most underrated EMI trick
A ₹1 lakh prepayment in year 2 of a ₹50L / 20-yr / 9% loan saves roughly ₹3 lakh in total interest. The same prepayment in year 18 saves almost nothing. Prepay early, prepay often.
On floating-rate housing loans, RBI rules ban prepayment penalties. On fixed-rate and personal loans, penalties of 2–4% may apply — still usually worth it. Use the Mortgage Payoff calculator to model the interest savings of an extra ₹X/month.
Considerations
- Total EMI commitments should stay under 40% of net monthly income. Banks will approve more (up to 65%); don't take it. You need a buffer for emergencies and lifestyle.
- Lower rate beats lower tenure for total interest savings. Refinancing from 9.5% → 8.5% on a ₹50L loan saves ~₹7 lakh; worth the paperwork.
- Pre-EMI period (when the property is under construction): you pay interest-only EMIs until possession. These are non-tax-deductible until the property is yours.
- Joint loans improve approval odds AND can give both co-borrowers Section 24(b) and 80C tax benefits.
Tax implications (India, old regime)
- Section 80C: Principal repayment up to ₹1.5 lakh/year (self-occupied home).
- Section 24(b): Interest paid up to ₹2 lakh/year (self-occupied; uncapped for let-out property).
- Section 80EEA: Additional ₹1.5 lakh for first-time buyers on loans under ₹35 lakh (subject to conditions).
- New regime: no home-loan deductions allowed. If you're paying significant home loan interest, the old regime usually wins. Verify with the Regime Compare calculator.
Limitations
- The calculator assumes constant interest rate over the tenure. Floating-rate loans get repriced quarterly. Re-run with the new rate when your bank revises.
- It doesn't model insurance bundling (PMAY-CLSS, group life insurance riders). These add 0.5–2% to effective cost.
- It doesn't model the time value of money on prepayments. Use the Mortgage Payoff tool for that.
- Processing fees (typically 0.5–1% of loan amount) and stamp duty are excluded. The APR calculator accounts for these.
Related calculators
- Mortgage Calculator — same math, home-loan-specific UX
- Amortization Schedule — full month-by-month breakdown
- Mortgage Payoff — model extra-payment scenarios
- Refinance Calculator — break-even on rate-change refinancing
- Auto Loan — same EMI math, with down payment + trade-in
- DTI Ratio — check whether you qualify before applying
Final note. The EMI itself is the boring part of the conversation. The interesting numbers are the total interest paid and the impact of prepayment. Run the math before you sign — and run it again every year of the loan, because every prepayment opportunity is leverage you'll never have again.
