Loan Calculator

Calculate the monthly payment, total interest and payment-by-payment schedule for any fixed-rate loan, whether personal, auto or student.

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years months

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Payment Every Month
Total of 120 Payments
Total Interest
■ Principal ■ Interest
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    Deferred Payment Loan: Paying Back a Lump Sum Due at Maturity

    years months

    Results:

    Amount Due at Loan Maturity
    Total Interest
    ■ Principal ■ Interest
    Show the calculation

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      Calculation Examples

      Calculation Case Result
      Personal loan $10,000, 3 years, 10% APR Monthly: $322.67 | Total interest: $1,616.19
      Auto loan $35,000, 5 years, 4.5% APR Monthly: $652.51 | Total interest: $4,150.34
      Student loan $25,000, 10 years, 5.0% APR Monthly: $265.16 | Total interest: $6,819.65
      Short-term: $5,000, 2 years, 12% APR Monthly: $235.37 | Total paid: $5,648.82
      Mihail Doncenco
      Mihail Doncenco Site Creator & Calculator Expert

      Founder and developer of CalcMate. Builds and maintains every calculator on this site, focusing on formula accuracy and clear, practical results.

      How to Use the Loan Calculator

      Enter the loan principal (the amount you borrow), the annual interest rate and the term in years or months. Click "Calculate" to apply the fixed-rate annuity formula: \[ M = P \dfrac{r(1+r)^n}{(1+r)^n - 1} \] where \(P\) is the principal, \(r\) is the monthly rate (annual rate divided by 12) and \(n\) is the number of monthly payments. You get the fixed monthly payment, the total interest over the term and a full amortization schedule.

      This calculator models standard fully amortizing, fixed-rate loans. For variable-rate loans, balloon payments or income-driven repayment plans on federal student loans, use a tool built for that product.

      How Does Loan Amortization Work?

      In a fixed-rate amortizing loan every payment is the same size, but its makeup changes. Interest is charged on the outstanding balance, so early payments are mostly interest, and as the balance shrinks the principal share grows.

      Take a $10,000 personal loan at 10% over 3 years. The payment is $322.67. The first payment is $83.33 interest and $239.34 principal. The last one is $2.67 interest and $320.01 principal. Total interest is $1,616.19. Because early payments are interest-heavy, extra principal in the first months does the most to cut total interest.

      Loan amortization: interest-to-principal ratio shifting over the loan term

      Useful Tips 💡

      • Compare offers by APR, not just the stated rate. APR adds origination fees and other finance charges to the interest rate, which makes offers with different fees comparable.
      • Pay extra principal early. In the first months the balance, and the interest charged on it, is at its highest, so each extra dollar saves the most.

      📋Steps to Calculate

      1. Enter the loan principal (amount borrowed).

      2. Enter the annual interest rate and the term in years or months.

      3. Click "Calculate" to see the monthly payment, amortization schedule and total interest.

      Mistakes to Avoid ⚠️

      1. Leaving out origination or processing fees. A 2% origination fee on a $20,000 loan adds $400 to the cost of borrowing.
      2. Entering the term in years as the number of payments. A 3-year loan needs n = 36. Entering n = 3 gives a payment of $3,389 instead of $322.67 on a $10,000 loan at 10%, about 10 times too high.
      3. Treating this calculator as a full mortgage estimate. It covers principal and interest only. A mortgage also needs property tax, insurance and PMI.
      4. Not revisiting your loan when rates or your credit score improve. Cutting the rate on a $35,000 five-year auto loan from 4.5% to 4.0% saves about $476 in interest.

      Practical Applications📊

      1. Compare the total cost of competing offers, not only the monthly payment. A loan with a lower rate and high origination fees can cost more than one with a slightly higher rate and no fees. APR, which US lenders must disclose under the Truth in Lending Act and Regulation Z, includes such finance charges.

      2. Test extra payments before you commit. Adding $50 a month to a $10,000 loan at 10% over 3 years cuts total interest from $1,616 to $1,366 and ends the loan 5 months early (31 payments instead of 36).

      3. Check affordability against income. A common guideline keeps total monthly debt payments under 36% of gross monthly income, though many lenders accept up to 43% or more.

      4. Plan repayment for installment, auto and personal loans: the schedule shows the interest and principal split of each payment, so you can time extra payments when early payoff matters.

      Questions and Answers

      Can I calculate student loan payments with this tool?

      Yes, for fixed-rate federal Direct Loans and private student loans on a standard repayment plan. A $25,000 loan at 5% over 10 years costs $265.16 a month and $6,819.65 in total interest. The tool does not fit income-driven plans, which set payments as a share of income. As of October 2026, the Repayment Assistance Plan (RAP) is available for federal Direct Loans, with payments of 1% to 10% of adjusted gross income and forgiveness after 30 years. PAYE, ICR and SAVE closed to new enrollees on July 1, 2026 and sunset by July 1, 2028, and loans first disbursed on or after July 1, 2026 can use only the standard plan or RAP. Check current details at studentaid.gov/loan-simulator.

      How do extra principal payments reduce loan cost?

      Extra principal lowers the balance right away, so every later month charges less interest. On a $10,000 loan at 10% over 3 years, an extra $50 a month saves about $250 in interest (from $1,616 to $1,366) and ends the loan 5 months early. The earlier you pay extra, the more you save, because the balance and the interest on it are highest at the start.

      How does interest affect total repayment?

      Interest is charged each month on the outstanding balance, so a higher rate, a longer term or a larger principal all raise total interest. On a $20,000 five-year loan, moving from 5% to 8% APR raises total interest from $2,645 to $4,332, a difference of $1,686 for the same principal and term. The amortization schedule shows the interest cost of each of the 60 payments.

      How does the loan term affect total cost?

      A longer term lowers the monthly payment but raises the total interest. On a $20,000 loan at 7%, a 3-year term costs $617.54 a month and $2,231.51 in interest. A 5-year term costs $396.02 a month and $3,761.44 in interest. That is about 36% less per month for about 69% more interest. Choose the shortest term whose payment you can comfortably afford.

      How is the monthly loan payment calculated?

      Put the principal \(P\), the monthly rate \(r\) (annual rate divided by 12) and the number of payments \(n\) (years × 12) into the amortization formula. For $10,000 at 10% over 3 years, \(r = 0.10 \div 12 = 0.008333\) and \(n = 36\), which gives a payment of $322.67. Lenders use the same math for their amortization tables.

      Is this calculator accurate for all loan types?

      It is accurate for fixed-rate, fully amortizing loans: the rate does not change, payments are equal and the loan is repaid in full by the end of the term. It does not fit variable-rate loans, balloon loans, interest-only loans or income-driven federal student loan plans. For those plans, use the Loan Simulator on studentaid.gov.

      What does a loan calculator compute?

      A loan calculator computes the monthly payment of a fully amortizing loan with the annuity formula \(M = P \dfrac{r(1+r)^n}{(1+r)^n - 1}\). It also builds the amortization schedule that splits each payment into interest and principal and totals the interest over the term. It suits personal, auto and fixed-rate student loans, which share one structure: fixed rate, fixed term, equal monthly payments.

      What is the difference between interest rate and APR?

      The interest rate is the yearly cost of the principal alone, and the APR adds fees to it. APR includes finance charges such as origination fees, discount points and processing charges, which gives one figure for comparing offers. US lenders must disclose the APR in consumer loan offers under the Truth in Lending Act and Regulation Z (12 CFR Part 1026). The rate alone can mislead when fees differ.
      Disclaimer: This calculator is designed to provide helpful estimates for informational purposes. While we strive for accuracy, financial (or medical) results can vary based on local laws and individual circumstances. We recommend consulting with a professional advisor for critical decisions.