Loan Payment Calculator
Calculate monthly payments for any loan — personal, auto, student, or business. See total interest, total cost, and payoff timeline. Free, instant, and private.
How Loan Payments Are Calculated
Fixed-rate loan payments use the same amortization formula as mortgages. The formula calculates a constant monthly payment that covers both principal repayment and interest charges over the loan term. Early in the loan, most of each payment goes to interest; as you pay down the principal, more goes to paying off the balance.
Loan Payment Formula
Monthly Payment = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1]
Where: P = principal, r = monthly rate (APR/12), n = total payments (years × 12)
Example Calculations
Auto Loan: $25,000 at 5.9% for 5 years
- Monthly: $482.16 | Total interest: $3,930 | Total: $28,930
Personal Loan: $10,000 at 8% for 3 years
- Monthly: $313.36 | Total interest: $1,281 | Total: $11,281
What Extra Monthly Payments Actually Save You
Every dollar you pay above the required monthly payment goes straight to principal, so it stops accruing interest for the rest of the loan. The saving compounds, which is why a small extra payment early beats a large one late. The calculator above has an optional Extra Payment field: enter what you can add each month and it re-amortises the loan and reports the new payoff date, the time saved, and the interest saved.
Worked example on the auto loan above — $25,000 at 5.9% over 5 years. The required payment is $482.16 and total interest is $3,930. Add $100 a month and the loan clears in 4 years 1 month instead of 5 years, total interest drops to about $3,151, and you keep roughly $779. You paid in $100 × 49 months of your own money and pulled 11 months off the term. Before committing, check the loan agreement for a prepayment penalty and confirm the lender applies extra money to principal rather than holding it as a prepaid future instalment — some auto and personal lenders default to the latter unless you tell them otherwise. Updated 2026-07-31.
Loan Types Compared
Auto loans: 3-7 years, 4-10% APR. Personal loans: 2-7 years, 6-36% APR. Student loans: 10-25 years, 4-8% APR. Business loans: 1-10 years, 6-30% APR. Rates depend on credit score, lender, and market conditions.
Tips for Getting Accurate Results
For the most accurate results, use up-to-date numbers from official sources. Double-check your inputs before calculating — small errors in the starting values can lead to significantly different outputs. If you are comparing scenarios, keep all variables the same except the one you are testing. Save or screenshot your results for future reference. This calculator uses standard formulas and is designed to give you a reliable quick estimate, though professional advice may be needed for complex situations.
Who Uses Loan Payment Calculator
Individuals use this tool to plan their personal finances, compare scenarios, and make informed money decisions. Freelancers and self-employed professionals use it to estimate their obligations and plan ahead. Students learning about personal finance find it helpful for understanding real-world numbers. Financial advisors sometimes use quick calculators like this as a starting point during client conversations. No matter your situation, having accurate numbers helps you make better financial decisions.
Frequently Asked Questions
How do I calculate my monthly loan payment?
Enter your loan amount, interest rate, and term. The calculator uses the standard amortization formula to compute your fixed monthly payment.
Does paying extra reduce total interest?
Yes, and the calculator now shows by how much. Extra payments go directly to principal, so the balance — and every future interest charge on it — shrinks faster. Enter an amount in the Extra Payment field and the tool re-amortises the loan and reports your new payoff date, time saved, and interest saved. On a $25,000 auto loan at 5.9% over 5 years, an extra $100 a month clears it 11 months early and saves about $779 in interest.
Will my lender apply an extra payment to principal?
Not automatically in every case. Some auto and personal lenders treat extra money as a prepaid future instalment, which does not reduce the interest you owe. Tell the lender in writing to apply extra amounts to principal, then check the next statement to confirm the balance dropped by the full extra amount. Also check the agreement for a prepayment penalty — these are uncommon on auto and personal loans but do still appear on some fixed-rate products.
What is the difference between APR and interest rate?
APR includes the interest rate plus fees and closing costs, annualized. It gives a more complete picture of the true cost of borrowing.
Is Loan Payment Calculator free to use?
Yes, Loan Payment Calculator is completely free with no sign-up, no login, and no hidden fees. The tool runs entirely in your browser — your data never leaves your device.
Is my data safe when using this tool?
Yes. This tool runs 100% in your browser using JavaScript. No data is sent to any server, stored in any database, or shared with any third party. When you close the page, processing stops immediately.