A reliable mortgage calculator makes planning home finance simple. Use this free calculator to estimate your monthly mortgage payment, see the total interest paid over the loan term, and view a full amortization schedule. You can also add extra monthly payments to see how they speed up the payoff and reduce interest.

How the calculator works

This tool uses the standard amortizing loan formula to calculate monthly payments from the loan amount, interest rate, and term. It computes how each payment splits between principal and interest and generates an amortization schedule showing the remaining balance after each payment. If you add an extra monthly payment, the calculator re-computes the schedule to show how many months you save and how much interest you avoid.

Why use a mortgage calculator

Before you apply for a loan or make an offer, knowing your monthly payment and total cost is crucial for budgeting and comparison shopping. A mortgage calculator helps you:
• Compare loan terms (15-year vs 30-year).
• Test different interest rates to see the impact on monthly payments.
• Model extra payments (biweekly or monthly) to shorten the loan and save interest.
• Estimate refinance savings by comparing current vs new interest rates and terms.

Key inputs and what they mean

• Loan amount (principal): the amount borrowed after your down payment.
• Interest rate: the annual nominal interest rate (enter the lender’s rate).
• Loan term: number of years to repay the loan.
• Extra payment (optional): additional monthly amount you’ll pay toward principal. Even small extra payments can shorten your loan by years and save thousands in interest.

Practical examples

1. 30-year vs 15-year: A lower-term loan (15 years) usually has a higher monthly payment but significantly less interest paid over time. Use the calculator to compare both scenarios side-by-side.
2. Extra payments: Adding $100 per month on a $300,000 loan at 4% reduces the term and interest paid — this calculator shows the exact savings.
3. Refinance estimate: Enter your current loan and a proposed new rate/term to quickly estimate monthly savings and the break-even point (how long until refinance costs are recovered).

Tips for smarter mortgage decisions

• Aim for a monthly housing cost (including taxes and insurance) that fits comfortably within your budget—many advisors suggest keeping total housing costs under 28–35% of gross monthly income.
• Consider shorter terms if you can afford the higher monthly payment — you’ll pay less interest and build equity faster.
• If interest rates drop significantly, run a refinance scenario to see whether refinancing makes financial sense after accounting for closing costs.
• Use the amortization schedule to plan additional principal payments when you have extra cash (bonuses or tax refunds).

When to talk to a lender or financial adviser

This calculator is a planning tool. For pre-approval, real interest quotes, and refinancing decisions that include closing costs and taxes, consult a mortgage broker or lender. If your financial picture is complex (self-employed income, investment properties), professional advice is recommended.