Loan & Mortgage Calculator
Calculate monthly payments, total interest, and view a full amortization schedule. Compare scenarios and see how extra payments save you money.
Extra Monthly Payment
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How It Works
- Enter your loan amount, interest rate, and term
- Adjust down payment to see its impact on monthly costs
- Add extra monthly payments to see interest savings and faster payoff
- Use Compare mode to evaluate different rate/term scenarios
- Review the amortization schedule (yearly or monthly view)
Features
- Standard amortization formula (fixed-rate)
- Donut chart showing principal vs. interest breakdown
- Extra payment analysis with time and interest savings
- Side-by-side scenario comparison
- Full amortization schedule (yearly or monthly)
- Presets for mortgage, auto, and personal loans
- All calculations performed locally in your browser
What is the Loan & Mortgage Calculator?
This free online loan and mortgage calculator lets you instantly compute monthly payments, total interest costs, and a full amortization schedule for any fixed-rate loan. It works entirely in your browser with no sign-up, no data uploads, and no limits on how many calculations you run.
Whether you are shopping for a home mortgage, financing a car, or evaluating a personal loan, this tool helps you understand the true cost of borrowing. You can compare scenarios side by side and see exactly how extra payments reduce your total interest and shorten your payoff timeline.
How to Use This Tool
Follow these steps to calculate your loan payments with this free online mortgage calculator:
- Select your loan type - Choose Mortgage, Auto Loan, or Personal to load sensible default values for each category
- Enter loan details - Set the loan amount, annual interest rate (APR), loan term in years, and your down payment percentage using the input fields or sliders
- Review your results - The right panel instantly shows your monthly payment, total amount paid, total interest, payoff date, and a donut chart breaking down principal versus interest
- Explore extra payments - Enter an additional monthly payment amount to see how much interest you save and how many months earlier you pay off the loan
- Compare scenarios - Click "Compare Scenarios" to enter a different rate or term and see a side-by-side comparison of monthly payment, total interest, and total cost
Key Features
- Full Amortization Schedule - View a complete payment breakdown by year or by month, showing exactly how much of each payment goes to principal versus interest
- Extra Payment Analysis - See precisely how additional monthly payments reduce total interest and accelerate your payoff date
- Side-by-Side Comparison - Evaluate different interest rates or loan terms against your current scenario to make informed decisions
- Three Loan Presets - Instantly switch between mortgage, auto loan, and personal loan defaults with appropriate ranges and values
- Visual Breakdown Chart - A donut chart displays your principal-to-interest ratio at a glance, helping you understand the true cost of borrowing
- 100% Client-Side - All calculations run locally in your browser; no financial data is ever sent to a server
Common Use Cases
Home buyers use this calculator to compare 15-year versus 30-year mortgage terms and understand how different down payment amounts affect monthly costs. Car shoppers evaluate dealer financing offers by entering the exact APR and loan term to see total interest before signing. Borrowers with existing loans use the extra payment feature to plan a payoff strategy that saves thousands in interest. Financial advisors and real estate agents share the tool with clients for quick, private estimates without requiring account creation or software installation.
Frequently Asked Questions
How accurate is this mortgage calculator?
This calculator uses the standard fixed-rate amortization formula that banks use. It computes monthly payments as P[r(1+r)^n] / [(1+r)^n - 1], where P is principal, r is the monthly interest rate, and n is total months. The result matches what lenders quote for fixed-rate loans. Note that it does not include property taxes, homeowner's insurance, or PMI, which are additional costs on top of the base mortgage payment.
How much can I save by making extra payments on my mortgage?
Even small extra payments make a significant difference over time. For example, on a $280,000 mortgage at 6.5% over 30 years, adding just $200 per month saves over $95,000 in interest and pays off the loan nearly 7 years early. Use the "Extra Monthly Payment" field to enter any amount and instantly see your projected savings in both dollars and time.
Is my financial data safe when I use this calculator?
Yes. This tool runs entirely in your browser using JavaScript. No data is transmitted to any server, no cookies are set, and no information is stored anywhere. You can verify this by using the tool while disconnected from the internet. It also works offline once the page has loaded.
What is the difference between a 15-year and 30-year mortgage?
A 15-year mortgage has higher monthly payments but dramatically lower total interest. Use the Compare Scenarios feature to see both side by side. For a $280,000 loan at 6.5%, the 30-year option costs about $357,000 in interest while the 15-year costs roughly $152,000, saving over $200,000. The trade-off is a monthly payment that is approximately 50% higher with the shorter term.
Can I use this calculator for auto loans and personal loans?
Absolutely. Click the "Auto Loan" or "Personal" tab at the top to load appropriate defaults (e.g., $35,000 at 7.5% for 5 years for auto, or $15,000 at 10% for 3 years for personal). The underlying math is identical for any fixed-rate installment loan. You can also manually enter any amount, rate, and term regardless of which tab is selected.