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What is EMI?
Published Apr 17, 2026
EMI stands for Equated Monthly Instalment — the fixed amount you pay every month until a loan is fully repaid. The key word is "equated": each payment is identical in size, even though the split between interest and principal changes every month.
How EMI is calculated
The standard EMI formula is derived from the present-value annuity formula:
EMI = P × r × (1 + r)^n / ((1 + r)^n − 1)
Where:
- P = Principal (loan amount)
- r = Monthly interest rate = annual rate ÷ 12 ÷ 100
- n = Total number of monthly payments = loan term in years × 12
Worked example
A $20,000 personal loan at 7% annual interest for 5 years:
- Monthly rate: r = 7 ÷ 12 ÷ 100 = 0.005833
- Number of payments: n = 5 × 12 = 60
- EMI ≈ $396.02/month
- Total paid over 5 years: $23,761
- Total interest paid: $3,761 (18.8% of the loan)
What happens inside each payment
Even though the EMI stays fixed, the interest portion shrinks and the principal portion grows with each payment. This is the essence of loan amortization:
| Payment # | Interest portion | Principal portion | Remaining balance |
|---|---|---|---|
| 1 | $116.67 | $279.35 | $19,720.65 |
| 12 | $108.89 | $287.13 | $18,624.42 |
| 30 | $94.55 | $301.47 | $16,066.26 |
| 60 (last) | $2.30 | $393.72 | $0.00 |
Early in the loan, most of your payment is interest. By the final payment, almost all of it is principal.
How each factor changes your EMI
| Change | Effect on EMI | Effect on total interest |
|---|---|---|
| Higher principal | Higher EMI | Higher total interest |
| Higher interest rate | Higher EMI | Higher total interest |
| Longer term | Lower EMI | Much higher total interest |
| Shorter term | Higher EMI | Much lower total interest |
| Extra payments | Unchanged (or optional recalculation) | Significantly lower — and loan ends sooner |
The total interest trap
A longer loan term lowers your monthly payment, but dramatically increases total interest paid:
- $100,000 at 6% for 10 years: EMI = $1,110 | Total interest = $33,224
- $100,000 at 6% for 20 years: EMI = $716 | Total interest = $71,943
- $100,000 at 6% for 30 years: EMI = $600 | Total interest = $115,838
The 30-year loan costs 3.5× the total interest of the 10-year loan, despite only having a 1.85× longer term.
EMI vs flat-rate interest
EMI uses the reducing-balance method — interest is calculated on the outstanding principal only. Some lenders quote a flat rate (interest calculated on the original principal for every period). A flat rate of 7% is equivalent to roughly 12–13% reducing-balance rate. Always clarify which method applies.
Use the Loan / EMI Calculator to calculate your exact monthly payment, see the full amortisation schedule, and model how extra payments shorten your loan term.