Extra-payment comparison
Add an extra monthly principal payment to compare payoff time and interest with the original repayment schedule.
Estimated payoff duration: 3 years · Add a start date to estimate a calendar payoff date.
Free loan calculator
Loan Calculator
Estimate your fixed-rate loan payment, total interest and payoff time. Explore personal, auto, student, business and other installment loan scenarios.
Compare the scheduled payment with optional extra principal payments, see a full amortization schedule and estimate upfront loan fees.
Calculator
Estimate your loan payment
Enter a loan amount, annual interest rate and term to see a monthly payment estimate. Your entries are calculated locally in your browser.
Loan balance over time
The balance declines as each payment pays down principal.
Remaining balanceCumulative principal paid
Remaining loan balance falls from $9,745.78 to zero over 36 monthly payments. Cumulative principal paid rises to $10,000.00.
Chart description: Remaining loan balance falls from $9,745.78 to zero over 36 monthly payments. Cumulative principal paid rises to $10,000.00.
Amortization schedule (36 payments)
Interest accrues first, then the scheduled payment is applied, followed by any extra principal payment. Payments and monthly interest are rounded to the currency’s standard fraction digits when posted, so the schedule totals reconcile with displayed amounts. The final payment is adjusted to the remaining balance.
| Payment | Payment Amount | Principal | Interest | Extra Payment | Remaining Balance |
|---|---|---|---|---|---|
| Year 1 summary | $3,650.64 | $3,135.94 | $514.70 | $0.00 | $6,864.06 |
| Payment 1 | $304.22 | $254.22 | $50.00 | $0.00 | $9,745.78 |
| Payment 2 | $304.22 | $255.49 | $48.73 | $0.00 | $9,490.29 |
| Payment 3 | $304.22 | $256.77 | $47.45 | $0.00 | $9,233.52 |
| Payment 4 | $304.22 | $258.05 | $46.17 | $0.00 | $8,975.47 |
| Payment 5 | $304.22 | $259.34 | $44.88 | $0.00 | $8,716.13 |
| Payment 6 | $304.22 | $260.64 | $43.58 | $0.00 | $8,455.49 |
| Payment 7 | $304.22 | $261.94 | $42.28 | $0.00 | $8,193.55 |
| Payment 8 | $304.22 | $263.25 | $40.97 | $0.00 | $7,930.30 |
| Payment 9 | $304.22 | $264.57 | $39.65 | $0.00 | $7,665.73 |
| Payment 10 | $304.22 | $265.89 | $38.33 | $0.00 | $7,399.84 |
| Payment 11 | $304.22 | $267.22 | $37.00 | $0.00 | $7,132.62 |
| Payment 12 | $304.22 | $268.56 | $35.66 | $0.00 | $6,864.06 |
| Year 2 summary | $3,650.64 | $3,329.38 | $321.26 | $0.00 | $3,534.68 |
| Payment 13 | $304.22 | $269.90 | $34.32 | $0.00 | $6,594.16 |
| Payment 14 | $304.22 | $271.25 | $32.97 | $0.00 | $6,322.91 |
| Payment 15 | $304.22 | $272.61 | $31.61 | $0.00 | $6,050.30 |
| Payment 16 | $304.22 | $273.97 | $30.25 | $0.00 | $5,776.33 |
| Payment 17 | $304.22 | $275.34 | $28.88 | $0.00 | $5,500.99 |
| Payment 18 | $304.22 | $276.72 | $27.50 | $0.00 | $5,224.27 |
| Payment 19 | $304.22 | $278.10 | $26.12 | $0.00 | $4,946.17 |
| Payment 20 | $304.22 | $279.49 | $24.73 | $0.00 | $4,666.68 |
| Payment 21 | $304.22 | $280.89 | $23.33 | $0.00 | $4,385.79 |
| Payment 22 | $304.22 | $282.29 | $21.93 | $0.00 | $4,103.50 |
| Payment 23 | $304.22 | $283.70 | $20.52 | $0.00 | $3,819.80 |
| Payment 24 | $304.22 | $285.12 | $19.10 | $0.00 | $3,534.68 |
| Year 3 summary | $3,650.60 | $3,534.68 | $115.92 | $0.00 | $0.00 |
| Payment 25 | $304.22 | $286.55 | $17.67 | $0.00 | $3,248.13 |
| Payment 26 | $304.22 | $287.98 | $16.24 | $0.00 | $2,960.15 |
| Payment 27 | $304.22 | $289.42 | $14.80 | $0.00 | $2,670.73 |
| Payment 28 | $304.22 | $290.87 | $13.35 | $0.00 | $2,379.86 |
| Payment 29 | $304.22 | $292.32 | $11.90 | $0.00 | $2,087.54 |
| Payment 30 | $304.22 | $293.78 | $10.44 | $0.00 | $1,793.76 |
| Payment 31 | $304.22 | $295.25 | $8.97 | $0.00 | $1,498.51 |
| Payment 32 | $304.22 | $296.73 | $7.49 | $0.00 | $1,201.78 |
| Payment 33 | $304.22 | $298.21 | $6.01 | $0.00 | $903.57 |
| Payment 34 | $304.22 | $299.70 | $4.52 | $0.00 | $603.87 |
| Payment 35 | $304.22 | $301.20 | $3.02 | $0.00 | $302.67 |
| Payment 36 | $304.18 | $302.67 | $1.51 | $0.00 | $0.00 |
| Total | $10,951.88 | $10,000.00 | $951.88 | $0.00 | $0.00 |
Year rows show grouped totals. Expand a year for monthly payment details. The table includes at most 600 monthly rows.
Loan basics
What is a loan calculator?
A loan calculator estimates regular payments and borrowing costs for a fixed-rate installment loan. It can help you compare possible amounts, rates and repayment terms before discussing an offer with a lender.
Monthly payment
The regular amount due each month under a fully amortizing fixed-rate schedule.
Total interest
The estimated cost of borrowing based on the rate and time the principal remains unpaid.
Payoff time
The number of monthly payments needed to bring the balance to zero, including extra principal payments when entered.
How to use the loan calculator
Start with the figures in a lender’s offer or enter a scenario you want to explore.
1. Loan Amount
Enter the amount you plan to borrow, before fees.
2. Annual Interest Rate
Enter the nominal annual rate used to calculate interest. APR may include certain fees.
3. Loan Term
Choose a whole number of years or months. The calculator converts it into monthly payments.
4. Extra Monthly Payment
Optionally enter an amount applied directly to principal after each scheduled payment.
5. Start Date and Fees
Add a start date to estimate payment dates. Expand optional fees to see upfront costs or finance them.
6. Review the estimate
Compare the scheduled payment, total interest, payoff time and amortization schedule.
How loan payments are calculated
Each regular payment covers interest accrued during the month and reduces the remaining principal.
M = P × [r(1 + r)n] ÷ [(1 + r)n − 1]
- M — Monthly payment
- The scheduled amount due before optional extra payments.
- P — Principal
- The financed amount, including fees only when you choose to finance them.
- r — Monthly rate
- Nominal annual interest rate ÷ 12 ÷ 100.
- n — Number of payments
- The term expressed as a number of monthly payments.
This is a fully amortizing loan: the scheduled payment is designed to repay principal and interest over the selected term. When the interest rate is zero, the payment is principal divided by the number of months. Early payments generally include more interest because the balance is larger; later payments apply more toward principal. Extra payments follow the order: monthly interest, scheduled payment, then extra principal.
Example calculation
For a $10,000 loan at 6% nominal annual interest over 36 months, the monthly rate is 0.5%. The estimated scheduled payment is about $304.22, for 36 scheduled payments and a final adjusted payment. The schedule totals about $10,951.88, including about $951.88 in interest. The unrounded formula gives approximately $10,951.90 total repayment; monthly cent rounding and the adjusted final payment account for the small difference.
Loan terminology
Principal versus interest
Principal is the borrowed amount still owed. Interest is the cost charged for borrowing it. Early in a typical amortizing loan, interest takes a larger share of each payment; as the principal falls, more of each payment reduces principal.
Interest rate versus APR
The interest rate is used to calculate interest on the outstanding balance. APR may include the rate and certain borrowing fees, allowing broader comparison. The calculator does not automatically reproduce a lender’s legally disclosed APR.
How extra payments help
Extra payments applied directly to principal can reduce future interest and shorten repayment because interest is calculated on a lower balance. The estimate assumes the lender allows this without a prepayment penalty.
Loan fees and net proceeds
Origination and processing fees increase borrowing cost. Fees paid upfront reduce the amount you receive; fees added to the loan increase principal, scheduled payments and interest. The calculator keeps fees separate unless you select financing.
What the estimate assumes
The loan has a fixed rate, regular monthly payments, full amortization, no payment holidays and no variable-rate changes. Extra payments go directly to principal, and no prepayment penalty is charged.
What is not included
The estimate excludes insurance, taxes, late fees, prepayment penalties, variable-rate changes, lender-specific rounding, compulsory products and other contract conditions. It is not mortgage-specific and excludes property taxes, homeowners insurance, HOA fees and mortgage insurance.
Frequently asked questions
What is a loan calculator?
A loan calculator estimates regular monthly payments and borrowing costs for a fixed-rate installment loan. It uses the amount, nominal annual interest rate, term, fees and any extra monthly principal payment you enter.
How is a monthly loan payment calculated?
The calculator converts the nominal annual interest rate to a monthly rate by dividing it by 12 and 100. It then uses the fixed-rate amortization formula to spread principal and interest over the selected number of monthly payments. At a 0% rate, principal is divided evenly across the term.
What is loan principal?
Principal is the amount borrowed. If you choose to finance fees, those fees are added to the principal used in the payment calculation.
What is an amortization schedule?
An amortization schedule shows each payment over time and how much goes to principal, interest and any extra principal, along with the remaining balance.
What is the difference between interest rate and APR?
The interest rate is used to calculate interest on the outstanding balance. APR may include the interest rate and certain borrowing fees. This calculator does not automatically reproduce a lender’s legally disclosed APR.
How does the loan term affect payments?
A longer term generally lowers each scheduled payment but can increase total interest because the balance is outstanding for more months. A shorter term generally raises the monthly payment and reduces the time interest accrues.
Do extra payments reduce interest?
Extra amounts are applied directly to principal after the scheduled payment. If the lender applies them this way, they can reduce the balance sooner, lower future interest and shorten repayment time.
Is there a penalty for paying a loan early?
Some lenders or loan agreements may charge prepayment penalties or have rules about how extra payments are applied. This estimate assumes no prepayment penalty; check your loan documents or ask your lender.
Does the calculator include loan fees?
You can enter an optional fixed fee or a percentage fee. Fees are paid upfront and reduce net proceeds unless you select Finance fees as part of the loan, which adds them to the financed principal.
Can I calculate a zero-interest loan?
Yes. At 0% interest, the loan amount is divided evenly across the scheduled monthly payments. Fees are still shown separately or included in principal if you choose to finance them.
Why is the lender’s payment different from this estimate?
A lender may use different rounding, payment dates, daily interest, fees, compounding conventions, optional products or contract terms. This calculator uses monthly payments and a nominal annual rate divided into 12 equal periods.
Can I use this for a mortgage?
This is a general fixed-rate installment loan calculator, not a mortgage payment calculator. It does not include property taxes, homeowners insurance, HOA fees or mortgage insurance.
Does changing currency convert the loan amount?
No. Selecting a currency changes number and symbol formatting only. The amount is not converted and no exchange rate is applied.
How is the final payment handled?
The schedule limits principal paid to the remaining balance and adjusts the final payment to the amount still owed, including that month’s interest. It stops once the balance reaches zero.
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Open calculator →Calculator disclaimer
This calculator provides an educational estimate, not a loan offer or financial advice. It assumes a fixed interest rate, regular monthly payments, a fully amortizing loan, no payment holidays, no variable-rate changes, and no prepayment penalty. Extra payments are applied to principal. Results do not automatically include insurance, taxes, late fees, lender-specific rounding, compulsory products or other loan conditions. Review the lender’s disclosures and loan agreement for actual terms.