Loan Calculator
Find the monthly payment and total interest on an auto loan, a personal loan or any fixed-rate installment loan. You also get a month-by-month amortization schedule.
Results are estimates. Your lender's figures may differ slightly because of fees, rounding or how interest is accrued. See our terms of use.
How to use this loan calculator
Enter the amount you plan to borrow, the interest rate you've been offered and the loan term. Auto and personal loan terms are usually given in months (36, 48, 60 or 72), so you can switch the term between months and years. The results update as you type.
If you plan to pay more than the required amount each month, enter it as an extra payment. The calculator shows your new payoff date and how much interest you'd avoid.
How loan payments are calculated
Most auto loans, personal loans and student loans are amortizing loans. You pay the same amount every month, and each payment covers that month's interest plus part of the principal. The payment comes from this formula:
M = P × r(1 + r)n ÷ [(1 + r)n − 1]
Here P is the amount borrowed, r is the monthly interest rate (the annual rate ÷ 12) and n is the number of payments.
Example: a $25,000 car loan at 7% for 60 months works out to $495.03 a month. Over five years you'd pay $29,701.80 in total, which includes $4,701.80 of interest.
Choosing a loan term
Stretching a loan over more months lowers the payment, but you pay interest for longer. Here's the same $25,000 loan at 7% with different terms:
| Term | Monthly payment | Total interest | Total paid |
|---|---|---|---|
| 36 months | $771.93 | $2,789.39 | $27,789.39 |
| 48 months | $598.66 | $3,735.49 | $28,735.49 |
| 60 months | $495.03 | $4,701.80 | $29,701.80 |
| 72 months | $426.23 | $5,688.21 | $30,688.21 |
Going from 36 to 72 months cuts the payment by about $346 but more than doubles the interest. In real life the gap is usually wider, because lenders often charge higher rates on longer terms. With car loans, a long term can also leave you owing more than the car is worth for years. That matters if the car is totaled or you want to sell it early.
Interest rate vs. APR
The interest rate is what your payment is calculated on. The APR (annual percentage rate) also includes certain fees, such as an origination fee, expressed as a yearly rate. That makes APR the better number for comparing loan offers, because a loan with a low rate and high fees can cost more than one with a slightly higher rate and no fees. Use the interest rate in this calculator to estimate your payment, and the APR to compare lenders.
Paying off a loan early
Extra payments reduce your principal right away, so every later month has less interest. Adding just $50 a month to the $25,000, 60-month loan above pays it off 6 months sooner and saves about $523 in interest.
Before paying extra, check two things:
- Prepayment penalties. Most auto and personal loans don't have them, but some do. Your loan agreement will say.
- How extra money is applied. Ask your lender to apply it to principal, not to next month's payment. Many online portals have a "principal only" option.
Common types of fixed-rate loans
- Auto loans: secured by the vehicle, usually 36–84 months. Rates depend on your credit, the loan term and whether the car is new or used.
- Personal loans: usually unsecured, often used to consolidate credit card debt or pay for large expenses. If a personal loan has a lower rate than your cards, it can save a lot of interest. You can compare the numbers with our credit card payoff calculator.
- Student loans: federal loans have fixed rates and several repayment plans, including income-driven options. This calculator shows a standard fixed-payment plan for whatever term you enter.
- Home equity loans: a lump sum borrowed against your home's equity, repaid like a second mortgage.
How to get a better rate
- Check your credit first. Your credit score is usually the biggest factor in the rate you're offered.
- Prequalify with several lenders. Many lenders show estimated rates using a soft credit check, which doesn't affect your score.
- Choose the shortest term you can afford. Shorter terms often come with lower rates.
- Ask about autopay discounts. Some lenders take a fraction of a percentage point off the rate if you pay automatically.
- For car loans, arrange financing before you shop so you can compare the dealer's offer with one you already have.
Frequently asked questions
Does this calculator work for interest-only or balloon loans?
No. It assumes a standard fixed-rate loan that is fully paid off by equal monthly payments. Interest-only and balloon loans have different payment structures.
My auto loan uses "simple interest." Is this still accurate?
Yes, closely. Many auto loans charge simple interest that accrues daily on the balance. The payment is set the same way, but the interest in a given month depends on exactly when your payment arrives. Paying a few days early saves a little interest, and paying late costs a little more.
Why does the last payment look smaller?
With extra payments, the final payment only needs to cover whatever balance is left, so it's usually less than a full payment.
Is the interest tax-deductible?
Personal loan interest generally isn't deductible. Some other loan interest can be, such as student loan interest, home equity interest when the money is used to buy, build or improve the home, and a temporary deduction for interest on certain new-car loans. The rules have income limits and other conditions, so check current IRS guidance or ask a tax professional.
Last reviewed: October 2026