Loan payment calculator — monthly payment & total interest

Reading the numbers before you sign

The monthly payment is what fits (or doesn't fit) in a budget, but total interest is what the loan actually costs. Stretching a car loan from 48 to 72 months lowers the payment while quietly raising the total cost — the calculator makes that trade-off visible before a lender does. Comparing two offers takes seconds: change the rate or the term and watch both numbers move.

Rates quoted by lenders are annual (APR for the headline rate); interest accrues monthly at one-twelfth of it. A difference that looks small — 6.5% against 7% — is about $30,000 of interest on a typical 30-year mortgage, which is why shopping the rate matters more than shopping the payment. The same monthly compounding works for you on savings — the compound interest calculator shows that side of the equation.

Mortgage vs car loan vs personal loan

The math behind all three is identical — fixed principal, fixed rate, fixed term — but the typical numbers differ. Mortgages run 15 to 30 years at the lowest rates because the property secures them. Car loans range from 36 to 72 months at slightly higher rates. Personal loans are shortest (12 to 60 months) and carry the highest rates because they are unsecured. Plugging each scenario into the calculator side by side makes the total interest difference impossible to ignore.

Before signing, compare at least three lender quotes — even half a percentage point matters over a long term. If you are a freelancer or small-business owner applying for a loan, having clean financial records helps: the invoice generator creates professional PDFs for your billing history. And if you are building an app that needs an AI cost estimate, the token calculator covers that too.

Frequently asked questions

How is the monthly loan payment calculated?

It uses the standard amortization formula: payment = P × r ÷ (1 − (1 + r)^−n), where P is the amount borrowed, r the monthly interest rate (annual rate ÷ 12) and n the number of monthly payments. A $250,000 loan at 6.5% over 30 years works out to about $1,580 per month. For a 0% loan the payment is simply the amount divided by the number of months.

What is an amortization schedule?

A month-by-month table splitting each payment into interest and principal, with the balance still owed after it. Early payments are mostly interest; the split flips as the balance falls. The schedule shows exactly where the tipping point is for your loan, and every 12th row marks a year end.

How much do extra payments actually save?

Any amount paid on top of the required payment goes straight to principal, so all future interest is charged on a smaller balance. On a 30-year $250,000 loan at 6.5%, an extra $100 a month saves roughly $56,000 in interest and pays the loan off about 4 years early. The extra-payment scenario computes the exact figures for your numbers.

Does this work for mortgages, car loans and personal loans?

Yes. The math is identical for any fixed-rate, fixed-term loan — enter the amount, the annual rate and the term. It does not model variable rates, interest-only periods or fees, so treat results as estimates and confirm exact terms with your lender.

Is my financial data uploaded anywhere?

No. Every calculation runs in your browser. Loan amounts and rates never leave your device, nothing is stored, and there is no sign-up.

What does Toolizto Pro add to the loan calculator?

The free tier computes the monthly payment, total interest, total cost and payoff date without limits. Pro ($9.99/month or $79.99/year, covering every Toolizto tool) adds the full amortization schedule, the extra-payment savings scenario, CSV export, and removes ads.