See every payment broken down — principal, interest, and remaining balance — for any loan, month by month.
Use this free amortization calculator to understand exactly where each EMI goes, how front-loaded the interest really is, and what you'd save by switching tenure or adding prepayments.
Direct answers to the most common questions, in plain language. Skim if you're in a hurry; dig deeper below.
How a loan is paid off — a fixed EMI each month, split between principal and interest.
Every EMI you pay covers two things: interest on the outstanding balance, and a portion of the principal. Early in the loan, most of the EMI goes to interest. Late in the loan, most goes to principal. That's amortization — and it's why prepaying early matters so much.
Because interest is calculated on the outstanding balance, which is highest at the start.
In month one of a 30-year home loan at 6.5%, roughly 90% of your EMI goes to interest and only 10% to principal. By month 360, it's flipped. The balance starts huge and shrinks slowly, so the interest math leans heavily on the early years.
Often more than the loan itself — sometimes significantly.
A 30-year home loan at 6.5% means you pay roughly 2.3× the original amount over the life of the loan. A 5-year auto loan at 7% costs about 1.2× the loan. The calculator shows the exact number for your situation.
Almost always yes, especially on long-tenure loans.
Even a small extra monthly payment shortens the loan dramatically and saves disproportionate interest. $100 extra per month on a 30-year mortgage can cut 3–5 years off the term and save tens of thousands. The calculator's extra-payment toggle shows the exact gain.
The mechanics in short answers — no jargon, no upsell.
Your monthly payment doesn't change over the life of the loan (assuming a fixed rate). What changes is how much of it pays down principal versus interest. The split shifts gradually toward principal as the balance falls.
Each month, the lender calculates interest on what you still owe. As you pay down principal, the next month's interest charge is slightly smaller — which means slightly more of the next EMI goes to principal. That compounding effect is what eventually clears the loan.
Lenders structure loans so the first half of the tenure is interest-heavy. Pay off the loan in year 5 of a 30-year mortgage and you've paid mostly interest, with limited equity built. This is why mid-loan refinancing rarely saves as much as people expect.
Any amount above the EMI goes 100% to principal, which reduces all future interest charges. A $5,000 lump-sum prepayment in year 1 saves vastly more than the same prepayment in year 20, because it stops 29 years of interest from accruing on that $5,000.
Designed so anyone can model their situation in under a minute, with or without a finance background.
The headline interest rate hides the total interest you'll actually pay over decades. The calculator surfaces the full number.
Knowing that 90% of early EMIs are interest changes how you think about prepayment, refinancing, and selling early.
A 20-year loan has a higher EMI but saves enormous interest over a 30-year loan. The calculator quantifies the gap.
See exactly how much each extra dollar saves you, and when in the loan tenure the impact is largest.
When considering refinance, you need to know what you've actually paid vs interest. The amortization schedule shows it cleanly.
In India and the US, home loan interest has tax implications. The calculator surfaces the year-by-year interest so you can plan deductions.
Everything you might ask before, during, or after using this tool.
EMI (equated monthly instalment) is the fixed monthly payment. Amortization is the schedule of how that EMI gets split between principal and interest, month by month, until the loan is fully repaid. Every amortizing loan has an EMI; the amortization is the underlying breakdown.
Most banks use day-count conventions (30/360, actual/365, etc.) that can produce minor differences from a textbook formula. The calculator uses the standard monthly amortization formula, which matches most lender quotes to within a few rupees or cents. Small differences over 30 years can compound to a few hundred dollars total — not material.
In a fixed-rate loan, no — the EMI stays the same for the entire tenure. In a floating-rate loan (more common in India for home loans), the EMI changes when the bank revises rates, typically every 3, 6, or 12 months. Most banks adjust the tenure rather than the EMI itself, but the option varies.
Depends on cash flow vs total cost. A 20-year mortgage has a higher EMI but saves dramatically on total interest — often $100K+ on a typical loan. A 30-year is easier on monthly cash flow but costs much more overall. The calculator lets you toggle between both and compare.
The lump sum goes directly to principal, reducing the outstanding balance immediately. From the next EMI onwards, the interest portion is lower (because the balance is smaller), so more of each future EMI flows to principal. The cumulative interest saved over the remaining tenure is far larger than the prepayment itself.
Yes — that's the "balance left" column in the amortization table. Subtract the current balance from the original loan amount to see how much principal you've actually paid. Many borrowers are surprised by how little this is in the early years of a long loan.
Because refinancing late in a loan tenure restarts the amortization clock with a fresh interest-heavy front-load. You may get a lower rate, but you also reset the schedule. The savings are real only if the rate gap is large enough and your remaining tenure is long enough to justify the reset.
It assumes a fixed rate throughout, which is the standard assumption for any amortization tool. For floating-rate loans, run the calculator with your current rate to get the baseline, and re-run when the rate changes. Most floating-rate loans behave like a series of fixed-rate amortizations stitched together.
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The structure isn't a conspiracy — it's a mathematical consequence of interest being calculated on the outstanding balance.
In month one of a 30-year, $300,000 loan at 6.5%, the outstanding balance is $300,000. Interest for that month is $300,000 × (6.5% / 12) = $1,625. The EMI is roughly $1,896, which means only $271 of the first payment goes to principal. The remaining $1,625 is pure interest.
By month 360, the balance is essentially zero, so the interest charge is minimal and almost the entire EMI flows to principal. The split has flipped completely over the tenure.
This is why mortgages and other long-tenure loans feel like you're "not making progress" in the early years. You are — but slowly, because the math is structured that way.
The standard EMI formula: EMI = P × r × (1 + r)^n / ((1 + r)^n − 1), where P is the principal, r is the monthly interest rate (annual rate ÷ 12), and n is the total number of months.
For a $300,000 loan at 6.5% over 30 years: P = 300,000, r = 0.005417, n = 360. Plug in and you get an EMI of $1,896. The total paid over 30 years is $682,633, of which $382,633 is interest.
The same loan at 7.5% gives an EMI of $2,098 and total interest of $455,089. A one-percentage-point rate increase costs $72,000 over 30 years. This is why the rate negotiation matters enormously, even when the monthly difference looks small.
Both, but in different ways.
A lower interest rate reduces the EMI directly. A shorter tenure reduces the total interest paid, but increases the EMI. The trade-off is usually framed as cash flow vs total cost.
Most borrowers underweight the impact of tenure. A 20-year mortgage at 6.5% on $300,000 has an EMI of $2,237 — about $341 more per month than the 30-year version. But total interest drops from $383K to $237K. That's $146,000 saved by paying $341 more per month for 20 years instead of $1,896 for 30.
If you can afford the higher EMI, shorter tenure almost always wins. If you can't, take the longer tenure and make voluntary prepayments — same financial effect, but with the flexibility to skip a prepayment in tight months.
The earlier in the loan, the better. A $10,000 prepayment in year 1 of a 30-year mortgage saves vastly more interest than the same prepayment in year 25.
Why: that $10,000 of principal would otherwise sit in the balance for 29 more years, accruing interest the entire time. Prepaying it in year 1 stops 29 years of compounding interest charges on that specific amount. In year 25, it only stops 5 years of interest accrual.
A useful rule of thumb: prepayments in the first third of the loan are roughly 3× more valuable than prepayments in the final third, in terms of interest saved per dollar.
This is also why refinancing is often less helpful than it seems. By the time you're 10 years into a 30-year loan, you've paid mostly interest and refinancing restarts the amortization clock. Voluntary prepayments on the existing loan often beat refinancing in this scenario.
Two short notes worth reading before you trust any number on this page.
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