Amortization Calculator
See your full loan payment schedule broken down by year. Understand exactly how much goes to principal vs. interest each period.
Yearly Amortization Schedule
| Year | Principal Paid | Interest Paid | Remaining Balance |
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Understanding Loan Amortization
Amortization is the process of spreading a loan into a series of fixed payments over time. Each monthly payment covers two components: a portion that reduces the principal balance and a portion that pays the interest charged by the lender. Understanding how amortization works is essential for anyone taking on a mortgage, auto loan, or personal loan because it reveals the true cost of borrowing and highlights opportunities to save money over the life of the loan.
How Payments Are Split Between Principal and Interest
When you make a fixed monthly payment on an amortized loan, the lender first applies the interest due for that period and then directs the remainder toward the principal. The interest portion is calculated by multiplying the outstanding balance by the monthly interest rate. In the early years of a long-term loan, the outstanding balance is at its highest, which means a large share of each payment goes toward interest rather than reducing what you actually owe. As you progress through the loan term and the balance shrinks, the interest charge decreases and a growing share of each payment chips away at the principal. This shifting ratio is exactly what an amortization schedule illustrates year by year.
Quick Reference: Amortization Key Facts
On a 30-year mortgage at 6.5%, roughly 75% of your first monthly payment goes to interest and only 25% to principal. By year 20, those proportions are nearly reversed. Making just one extra payment per year on a 30-year mortgage can shorten the loan by approximately 4 to 5 years and save tens of thousands in interest. The standard amortization formula is M = P[r(1+r)^n] / [(1+r)^n - 1], where P is principal, r is the monthly rate, and n is the total number of payments.
Front-Loading of Interest
Lenders structure amortized loans so that interest is front-loaded, meaning borrowers pay the most interest during the earliest years of the loan. This design is not arbitrary; it reflects the mathematical reality that interest accrues on the full outstanding balance. For a typical 30-year mortgage, a borrower may pay more in total interest during the first ten years than the remaining twenty combined. This front-loading effect is why refinancing or selling a property only a few years into a mortgage can feel financially discouraging -- much of the money paid has gone to the lender as interest, and the principal balance has barely budged. Recognizing this pattern empowers borrowers to make more informed decisions about loan terms, down payments, and whether shorter loan durations might be worthwhile despite higher monthly payments.
The Power of Extra Payments
One of the most effective strategies for reducing total borrowing costs is making extra payments toward the principal. Because interest is calculated on the remaining balance, every additional dollar applied to principal reduces the base on which future interest accrues. Even modest extra payments, such as rounding up to the nearest hundred or adding a small fixed amount each month, compound over time into substantial savings. For example, adding an extra $100 per month to a $250,000 mortgage at 6.5% can save over $60,000 in interest and cut nearly six years off the repayment period. Before making extra payments, borrowers should confirm with their lender that there are no prepayment penalties and that the additional amount is applied directly to principal rather than being held for future scheduled payments.