calculate-loan

01 Loan payments

Personal Loan Calculator Payment Amount

Calculator No. 01-6935 · Updated · Formula and assumptions shown below

Monthly payment $405.53
Total interest
$4,331.80
= Monthly payment × loan term × 12 − loan amount
Loan amount
$20,000
Input
Interest rate (APR)
8 %
Input
You enter
Loan amount ($), Interest rate (APR) (%), Loan term (years)
You get
Monthly payment ($), Total interest ($)
Rounding
2 dp

Estimate for education, not financial advice. The result follows from the numbers you enter and the formula shown. It is not a quote or an offer, and it does not include fees, taxes or insurance unless the calculator asks for them. Ask your lender for the exact figures.

A personal loan calculator estimates your monthly payment from the amount borrowed, annual percentage rate (APR), and loan term; it also estimates total interest. Enter the loan’s disclosed figures to see a level-payment estimate, not an offer or approval decision.

Formula

The calculator uses the standard amortizing-loan payment formula, with monthly payments and a fixed rate:

Payment = P × r ÷ [1 − (1 + r)−n]

  • P is the principal, or loan amount, in dollars.
  • r is the monthly interest rate, calculated as APR ÷ 1,200. APR is entered as a percentage per year.
  • n is the number of monthly payments, calculated as years × 12.
  • Payment is the estimated monthly payment in dollars, rounded to the nearest cent.

Total interest is calculated as the rounded monthly payment multiplied by the number of payments, minus the original loan amount: Total interest = Payment × n − P. The displayed total therefore uses the payment rounded to cents, as scheduled payment amounts generally are. A final payment can differ slightly from the regular payment because of rounding or lender-specific calculations.

Worked Example

Using the calculator’s default inputs—$20,000 borrowed, 8% APR, and a five-year term:

  1. Convert the APR to a monthly rate: 8 ÷ 1,200 = 0.0066667.
  2. Find the payment count: 5 × 12 = 60 monthly payments.
  3. Substitute into the formula: $20,000 × 0.0066667 ÷ [1 − (1 + 0.0066667)−60].
  4. The monthly payment is approximately $405.53.
  5. Using the rounded payment, total paid is $405.53 × 60 = $24,331.80, so estimated total interest is $24,331.80 − $20,000 = $4,331.80.

Assumptions

  • The APR stays fixed throughout the full term.
  • Payments are equal, made monthly, and applied at regular intervals.
  • Interest accrues monthly using APR divided by 12.
  • Fees, taxes, insurance, and other charges are not included; the calculation assumes the entered loan amount is the principal being repaid.

How to Read the Payment Estimate

The monthly payment is the scheduled principal-and-interest amount under these assumptions. It is not necessarily the total amount due each month if the loan has separate charges or a different payment schedule. The total interest figure is the estimated interest over the full term if every payment is made as modeled; it is not an additional monthly cost.

Loan amount, APR, and term affect the result in different ways. A larger principal raises the payment when the other inputs are unchanged. A higher APR also raises it. Extending the term usually reduces the scheduled monthly amount, but provides more months for interest to accrue and may increase total interest. A shorter term usually has larger scheduled payments and fewer payment periods. These are mathematical effects, not a recommendation about which arrangement to use.

What to Enter and Common Calculation Issues

Use the loan amount and APR shown in the lender’s offer or disclosure, and check whether any fee is financed into the principal. Enter APR as a percentage: type 8 for 8%, not 0.08. The calculator converts annual APR to a monthly decimal rate internally. Enter the term in years; for a term stated in months, divide the number of months by 12.

  • Comparing different loan amounts: A payment comparison is meaningful only when the principal, APR, term, and included costs are understood. A lower payment alone does not establish a lower total cost.
  • Rounding too early: The displayed payment is rounded to cents. Calculations using unrounded intermediate values may differ by a few cents from totals based on the displayed payment.
  • Confusing APR and monthly rate: Do not enter a monthly rate in the APR field. The formula divides the annual percentage by 1,200.
  • Leaving out charges: Origination or other fees may be paid separately or added to the amount financed. The calculator does not determine how a lender treats them; use the disclosed principal and charges.

Limits and Related Loan Questions

This estimate models a conventional level-payment loan: the same payment is due each month, and each payment covers interest accrued plus some principal. It does not model a changing rate, irregular payment dates, skipped or late payments, prepayment charges, extra payments, or a final payoff quote. Actual interest may depend on the lender’s day-count method, transaction dates, payment posting, and contract terms.

A personal loan payment calculator is useful for understanding the arithmetic of a stated offer, but it cannot establish what rate or amount a person may receive. Rates, fees, term availability, and approval conditions depend on the lender and the specific application. Obtain the actual figures from the lender and review the loan disclosure for charges and payment details.

Frequently Asked Questions

How do you calculate a personal loan payment?
Convert APR to a monthly decimal rate by dividing the percentage by 1,200, convert the term to months, and apply the amortizing-payment formula shown above. The calculator performs these steps and rounds the payment to cents.

Does a longer personal loan term lower the monthly payment?
For the same principal and APR, a longer term generally spreads repayment across more monthly payments, reducing each scheduled payment. It also means interest accrues for more periods, which can raise total interest.

Does the payment include loan fees?
Not automatically. The estimate uses the principal and APR entered and excludes separate charges. If a fee is financed, check whether it is included in the disclosed loan amount before entering the principal.

Why is my lender’s payment different from the calculator?
The lender may use different dates, rounding, fees, a different principal or APR, or payment terms not represented by this fixed-rate monthly model. Compare the calculator inputs with the disclosure and ask the lender how its scheduled amount is calculated.

Is APR the same as the monthly interest rate?
No. APR is an annual percentage measure. This calculator converts it to a monthly rate by dividing by 12 and by 100, represented together as APR ÷ 1,200.

This result is an estimate, and the lender’s disclosure gives the exact figures.

Related

Formula used
in p | Loan amount | $ | 20000 | 1 | 100000000
in apr | Interest rate (APR) | % | 8 | 0.01 | 100
in yrs | Loan term | years | 5 | 0.0833 | 50
out pmt | Monthly payment | $ | round(p * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)), 2) | 2
out int | Total interest | $ | pmt * yrs * 12 - p | 2

Each line is one input (in, sel, list) or one result (out: label, unit, formula, decimals). How the calculators work

Method: the standard loan formula for this calculation, fixed rate and monthly compounding unless stated, rounded as each result states. Not financial advice; no lender, rate or product is recommended. See formulas and assumptions, the disclaimer or report an error.

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