What is Loan / Mortgage Calculator?

Calculates your monthly payment, total interest, and amortization schedule for any fixed-rate loan. Compare different loan amounts, rates, and terms to see how each option affects what you pay.

Enter principal, annual rate, and term in years. The calculator uses the standard amortization formula to break each scheduled payment into principal and interest, then totals the cost over the life of the loan. The amortization table shows every payment so you can see how the interest portion shrinks as the balance falls.

How to use

1. Enter the loan principal amount, annual interest rate, and loan term in years to instantly see your monthly payment breakdown.
2. Review the amortization table to see exactly how much of each payment goes toward principal versus interest over time.
3. Adjust the values to compare scenarios — try a 15-year versus 30-year term to see the difference in total interest paid.

When to use

• Comparing a 15-year vs 30-year mortgage before locking in a rate with a lender.
• Sanity-checking the monthly figure a car dealer or broker quoted you.
• Estimating how much an extra principal payment trims off the total interest.

Result

You're considering a $350,000 mortgage at 6.5% for 30 years. The calculator shows a $2,212 monthly payment with $446,247 in total interest. Switching to 15 years raises the payment to $3,049 but saves $197,396 in interest.

FAQ

Does this account for property taxes, insurance, and HOA fees?

Yes. Enter your annual property tax and home insurance, plus monthly HOA dues, and the Estimated Monthly Cost card adds them on top of principal and interest. If your down payment is under 20%, a PMI field appears too. As a rough guide, taxes and insurance together run about 1.0 to 1.5% of the home value per year.

Why is so much of my early payment going to interest?

Interest each month equals balance times monthly rate. On a $350k loan at 6.5%, the first month's interest is about $1,896. As the balance drops the interest portion shrinks and the principal portion grows. The crossover happens around year 18 on a 30-year term.

Does the calculator support adjustable-rate or variable-rate loans?

It assumes a fixed rate for the full term. For an ARM, calculate the initial period using the teaser rate and the post-reset period using the worst-case rate from your disclosure. Add the two payment streams to see your potential cost.

How much does paying biweekly really save?

Biweekly means 26 half-payments a year, which equals one extra full payment annually. On a 30-year, 6.5%, $350k loan that trims roughly 5 years and around $100,000 in interest off the total. Enter your loan and the Biweekly Payment Plan panel shows your exact half-payment, how much sooner you finish, and the interest you save.

Can I use this for student loans or personal loans?

Yes. The math is identical for any fixed-rate amortizing loan. Set the term in years (use decimals if needed, like 5.5 for 66 months) and enter the rate the lender quoted. Federal student loans with income-driven plans need a different model.

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