Amortization Schedule Calculator
Amortization Schedule Calculator
Select a preset to auto-fill typical values, or enter custom values below
The total principal amount borrowed
How often you make payments
Enter Your Loan Details
Fill in the loan amount, interest rate, and term above to generate your complete amortization schedule with payment-by-payment breakdown.
Important
This calculator is provided for general information only and is not financial, tax, or legal advice. Results are estimates and do not reflect your full circumstances, current rates, fees, or eligibility rules. Speak to a qualified professional before making a financial decision.
Calculate your full loan payment schedule with interest breakdown and extra payment savings
An amortization schedule calculator is one of the most powerful personal finance tools available. Whether you are taking out a mortgage, financing a car, consolidating student loans, or planning a personal loan, understanding how your payments are allocated between principal and interest over time is essential for making informed financial decisions. Our free amortization schedule calculator generates a complete payment-by-payment breakdown instantly, right in your browser — no sign-up required. Every loan payment you make consists of two parts: a portion that reduces your principal balance and a portion that pays the interest charged for that month. In the early years of a loan, the vast majority of each payment goes toward interest, with only a small slice reducing what you actually owe. Over time, this ratio flips — by the final years, most of your payment is reducing the principal. This phenomenon, known as amortization, is why it often feels like your loan balance barely moves in the first few years. Our calculator goes far beyond a simple monthly payment figure. Enter your loan amount, annual interest rate, loan term, and optional loan start date, and you will see your complete monthly amortization table. Each row shows the payment date, total payment amount, how much goes to interest, how much reduces your principal, and your remaining balance after that payment. You can also switch to an annual summary view to see year-by-year totals at a glance. One of the most financially impactful things you can do with this calculator is model extra payments. Adding even a small amount each month — say, $100 to $200 — can shave years off your loan and save tens of thousands of dollars in interest. Our calculator lets you add extra monthly payments, extra annual lump-sum payments, and a one-time extra payment, then immediately shows you how many months you save and how much interest you avoid. The side-by-side comparison panel makes the savings crystal clear. We also support multiple payment frequencies — monthly, biweekly, weekly, semimonthly, quarterly, semiannually, and annually — so you can accurately model loans with non-monthly payment schedules. The biweekly option is particularly popular because making 26 biweekly payments is equivalent to making 13 monthly payments per year, effectively making one extra payment per year and significantly shortening the loan term. For visual learners, the calculator includes a donut chart showing the total principal versus total interest breakdown, and a line graph plotting your remaining balance over the life of the loan. You can also use our rate scenario panel to see how your payment changes at different interest rates, helping you compare offers from multiple lenders. Once you have your results, you can export the full amortization table to a CSV file for use in Excel or Google Sheets, print a clean version for your records, or copy a summary to your clipboard. Loan type presets for mortgage, auto loan, personal loan, and student loan pre-fill typical terms and rates to get you started quickly.
Understanding Loan Amortization
What Is an Amortization Schedule?
An amortization schedule is a complete table listing every payment of a loan from the first payment to the last. Each row in the table shows the payment number, the payment date, the total amount paid, how much of that payment goes to interest, how much reduces the principal balance, and the remaining balance after the payment is applied. For a standard 30-year mortgage, this means 360 rows — one for each monthly payment. The schedule shows you exactly when your loan will be paid off and how much interest you will pay in total over the life of the loan. Most lenders provide a basic amortization schedule at closing, but an online calculator lets you experiment with different scenarios before you commit. Understanding your amortization schedule helps you make smarter decisions about when to refinance, whether to make extra payments, and how different loan terms affect your total cost.
How Is the Payment Calculated?
The standard amortization payment formula is M = P × [r(1+r)^n] / [(1+r)^n - 1], where M is the fixed monthly payment, P is the principal (loan amount), r is the periodic interest rate (annual rate divided by number of periods per year, divided by 100), and n is the total number of payments. For example, a $300,000 mortgage at 7% annual interest for 30 years has r = 0.07/12 = 0.005833 and n = 360. This gives a monthly payment of approximately $1,996. Each period, the interest charge is calculated as the current balance multiplied by the periodic rate. The remainder of the payment reduces the principal. This process repeats until the balance reaches zero. The final payment is often slightly different due to rounding, so calculators apply a final-payment correction to ensure the balance ends at exactly zero.
Why Extra Payments Matter So Much
Because interest compounds on the outstanding balance, reducing the principal early has an outsized effect on your total interest paid. Consider a $300,000 mortgage at 7% for 30 years: the total interest paid is approximately $418,500. But if you add just $200 per month in extra principal payments, you save roughly $73,000 in interest and pay off the loan nearly 5 years early. The savings grow exponentially with the extra amount because every dollar of principal you eliminate today prevents years of future interest charges. This is the core reason financial advisors often recommend making at least small extra principal payments when possible. Our calculator lets you see the exact impact of any extra payment amount so you can make this decision with full information rather than guesswork.
What This Calculator Does Not Include
This calculator computes the pure principal and interest amortization for a standard fixed-rate loan. It does not include property taxes, homeowner's insurance, PMI (private mortgage insurance), or HOA fees — costs that are part of a full PITI mortgage payment. It also assumes a fixed interest rate for the entire loan term, so it is not suitable for adjustable-rate mortgages (ARMs) where the rate changes after an initial fixed period. The calculator also assumes payments are made on time every period; missed or partial payments would alter the actual schedule. For variable-rate loans, refinancing scenarios, or loans with balloon payments, consult a financial advisor or use a specialized tool. The results here are estimates for planning purposes and do not constitute financial advice.
How to Use the Amortization Schedule Calculator
Enter Your Loan Details
Start by entering your loan amount (the total amount borrowed), annual interest rate, and loan term in years. For a 30-year mortgage at 7%, enter 300000, 7, and 30. Use a loan type preset to auto-fill typical values for mortgage, auto, personal, or student loans.
Choose Payment Frequency and Start Date
Select how often you make payments — monthly is standard for most loans, but biweekly can save significant interest. Set your loan start date to see exact payment dates in your amortization table. The payoff date will be calculated automatically.
Add Extra Payments to See Savings
Enter an extra monthly payment, annual lump-sum, or one-time payment to model prepayment. The calculator instantly shows how many months you save, how much interest you avoid, and your new payoff date. The side-by-side comparison panel makes the savings clear.
Review the Schedule and Export
Scroll through your monthly or annual amortization table to see the exact payment, principal, interest, and balance for every period. Use the Rate Scenarios tab to compare different interest rates. Export the full schedule to CSV or print it for your records.
Frequently Asked Questions
What is an amortization schedule and why do I need one?
An amortization schedule is a complete table showing every payment of your loan — the date, payment amount, how much goes to interest, how much reduces your principal, and your remaining balance. You need one because it reveals the true cost of borrowing. For a 30-year mortgage, you might be surprised to learn that over the first 5 years, only about 15-20% of your payments go to reducing what you owe — the rest goes to interest. This knowledge helps you make informed decisions about prepayment, refinancing, and whether a shorter loan term is worth the higher monthly payment.
How much can I save by making extra principal payments?
Extra payments can save a surprising amount. On a $300,000 mortgage at 7% for 30 years, adding just $100 per month in extra principal saves approximately $36,000 in interest and pays off the loan about 3.5 years early. Adding $300 per month saves roughly $89,000 and cuts 8 years off the term. The savings compound because every dollar of principal you eliminate today eliminates all future interest on that dollar. Use our calculator's extra payment section to enter your specific amounts and see the exact impact for your loan.
Is biweekly payment better than monthly?
Biweekly payments are an effective strategy that many homeowners use to pay off their mortgage faster without feeling a large budget impact. By paying half your monthly payment every two weeks, you end up making 26 half-payments per year — equivalent to 13 full monthly payments instead of 12. That one extra payment per year goes entirely to principal. On a $300,000 mortgage at 7% for 30 years, biweekly payments can save roughly $57,000 in interest and cut about 5 years off the term. Check with your lender to ensure they apply biweekly payments immediately rather than holding them until month-end.
Why does so little of my early payments go to principal?
This is the nature of amortization and is sometimes called being 'upside down' on a loan in its early stages. Since interest is calculated on the outstanding balance, and the balance is highest at the beginning of the loan, the interest charge is highest in the early payments. On a 30-year mortgage, it can take 18-20 years before more than half of each payment goes to principal. This is why refinancing in the early years of a loan can sometimes be beneficial — if rates drop significantly, you restart with a lower payment without losing too much built-up equity. Our amortization table shows exactly how the principal/interest split changes each year.
What is negative amortization and should I worry about it?
Negative amortization occurs when your loan payment is less than the interest charged for that period. Instead of the balance going down, it actually grows — the unpaid interest is added to the principal. This is most common with certain adjustable-rate mortgages, interest-only loans, or if you choose a very low payment option. Standard fixed-rate loans always have payments set high enough to avoid this. Our calculator displays a warning if you enter values that would cause negative amortization, alerting you before you commit to a loan structure that increases your debt over time rather than paying it down.
How do I use this calculator for a car loan or personal loan?
This calculator works for any standard fixed-rate amortizing loan — not just mortgages. For a car loan, select the Auto Loan preset (typically 5 years at 6% APR) or enter your specific rate and term. For a personal loan, use the Personal Loan preset (typically 3 years at 11%) or enter your lender's terms. The amortization math is identical regardless of loan type. The key differences are just the interest rate and term length. Car loans typically run 36-72 months, personal loans 12-84 months, and mortgages 10-30 years. Enter the exact values from your loan offer to see the precise payment and total cost.