Calculate loan amortization schedules showing monthly payment breakdown of principal, interest, extra payments, and remaining balance over time.
An amortization calculator breaks down every payment over the life of a loan into principal and interest portions. This visibility is crucial for understanding where your money goes each month — early payments are mostly interest, while later payments chip away at principal.
Understanding amortization helps you make smarter borrowing decisions. By seeing the full schedule, you can evaluate whether making extra payments, refinancing, or choosing a shorter term will save you significant money. Even small extra payments early in a loan's life can shorten the term by years and save tens of thousands in interest.
This calculator generates a complete amortization schedule for any fixed-rate loan. Enter your loan amount, interest rate, and term to see every payment broken down. Add optional extra monthly payments to see how much interest you save and how many months you cut off the loan. The visual breakdown and detailed table give you full transparency into the true cost of borrowing.
Most borrowers only know their monthly payment — they never see the breakdown. This calculator reveals how much of each payment goes to interest versus principal, the total interest cost, and the impact of extra payments on payoff timing. That helps you compare standard repayment with accelerated payoff strategies and see the real cost of the loan.
Monthly Payment M = P × [r(1+r)^n] / [(1+r)^n − 1], where P = principal, r = monthly interest rate (annual rate / 12 / 100), n = total number of payments. Each payment splits: Interest = Balance × r, Principal = M − Interest.
Result: $1,580.17/month — $318,860 total interest — $568,860 total payments
A $250,000 loan at 6.5% for 30 years has a monthly payment of $1,580.17. Over 360 payments, you pay $568,860 total — $318,860 of that is interest. Adding even $100/month in extra payments would save over $50,000 in interest and pay off the loan 5+ years early.
An amortization schedule shows how each payment is split between interest and principal from the first month to the last. Early payments lean heavily toward interest because the balance is highest, while later payments shift toward principal as the remaining balance falls.
Extra payments reduce the balance faster, which lowers the interest charged on future payments. Even modest extra amounts can shorten the term noticeably, especially when they are made early in the loan. This makes the schedule useful for comparing standard repayment against aggressive payoff plans.
Fixed-rate amortizing loans are only one repayment style. Interest-only loans delay principal reduction, balloon loans leave a large final balance, and adjustable-rate loans can re-amortize when the rate changes. Use the schedule to see which structure fits your repayment plan and risk tolerance.
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This worksheet applies the standard amortization formula for fixed-rate installment loans. It calculates a level payment from the principal, periodic interest rate, and term, then allocates each payment between interest and principal until the balance reaches zero.
Extra payments are applied directly to principal. The schedule is intended for repayment planning and scenario comparison, not lender disclosures or individualized credit advice.
Amortization is the process of spreading a loan into fixed payments over time. Each payment covers interest on the remaining balance plus a portion of principal. Early payments are mostly interest; later payments are mostly principal.
Each month, interest is calculated on the remaining balance. The rest of your fixed payment reduces the principal. As the balance shrinks, less goes to interest and more to principal — this is why the schedule shifts over time.
Interest is calculated on the outstanding balance. At the start, the balance is at its maximum, so interest charges are highest. As you pay down principal, interest decreases and more of each payment reduces the balance.
On a $250,000 loan at 6.5% for 30 years, an extra $200/month saves approximately $95,000 in interest and pays off the loan about 9 years early. The savings depend on your rate, balance, and how early you start making extra payments.
Amortized loans have fixed payments that include both principal and interest, with the split changing each period. Simple interest loans charge interest only on the original principal (or current balance) without the structured payment schedule.
Yes — this works for mortgages, auto loans, personal loans, student loans, or any fixed-rate amortizing loan. It does not apply to interest-only loans or revolving credit like credit cards.