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01 Loan payments

Personal Loan Repayment Schedule Calculator

Calculator No. 01-4100 · Updated · Formula and assumptions shown below

Monthly payment $405.53
Total interest
$4,331.67
= 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.

This personal loan repayment schedule calculator estimates your fixed monthly payment and total interest from the loan amount, APR and term. Enter the figures from a lender’s loan disclosure to see the payment-based estimate; the schedule assumes regular monthly payments and a fixed rate.

Formula

The calculator uses the standard fixed-payment amortization formula. It divides the loan principal and interest into equal monthly payments over the selected term:

Monthly payment = P × r ÷ [1 − (1 + r)−n]

  • P is the amount borrowed, 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.

Total interest is estimated as monthly payment × number of payments − principal. The displayed payment is rounded to cents, and the interest calculation uses that displayed payment. This is a useful estimate; a lender’s precise schedule may differ because of its payment dates, rounding, fees or other loan terms.

Worked Example

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

  1. Convert APR to a monthly decimal rate: 8 ÷ 1,200 = 0.0066667.
  2. Find the payment count: 5 × 12 = 60 months.
  3. Substitute into the formula: $20,000 × 0.0066667 ÷ [1 − (1.0066667)−60].
  4. The monthly payment is approximately $405.53.
  5. Using the rounded monthly payment, total payments are $405.53 × 60 = $24,331.80; estimated total interest is $24,331.80 − $20,000 = $4,331.80.

Assumptions

  • The interest rate is fixed for the entire loan term.
  • Payments are equal, made monthly, and made at the end of each monthly period.
  • Interest accrues monthly at APR divided by 12.
  • The estimate excludes fees, taxes, insurance and other charges; none are entered in this calculator.

How a Personal Loan Repayment Schedule Works

A repayment schedule, also called an amortization schedule, shows how each payment is divided between interest and principal. At the beginning of a standard fixed-rate loan, the balance is larger, so more interest accrues for that period. As principal is repaid, the balance falls and the interest portion generally becomes smaller. With a level payment, the principal portion generally grows over time.

For example, at the start of the default example, monthly interest on $20,000 at 8% APR is about $133.33 ($20,000 × 0.08 ÷ 12). Of the $405.53 payment, roughly $272.20 would therefore reduce principal, before any lender-specific rounding or charges. In a later month, interest is calculated on a smaller remaining balance. The payment itself stays level under the calculator’s assumptions.

The two calculator results answer different questions. Monthly payment estimates the recurring scheduled amount. Total interest estimates the borrowing cost over all scheduled payments, excluding fees and other charges. The principal is not interest: it is the amount borrowed that the payments repay.

How to Read and Use the Estimate

Use the amount actually financed, not necessarily the amount you intend to receive. A fee deducted from proceeds or added to the balance can make those figures different; check the disclosure for the principal used to calculate payments. Enter APR as a percentage, such as 8 for 8%, rather than 0.08. Enter the term in years. The calculator converts it into monthly payments.

  • Compare the estimated payment with the payment amount stated in the lender’s disclosure.
  • Check whether the lender uses a fixed or variable rate. This formula assumes fixed interest and does not model a changing rate.
  • Review the payment dates, first-payment timing, fees and any optional add-ons separately.
  • Use the disclosed schedule for exact due dates, balances and payoff figures.

A longer term usually means more scheduled payments and, when the rate and principal are held constant, more total interest under this model. It also generally lowers the calculated monthly payment. This is a mathematical relationship, not a judgment about which term is appropriate for an individual.

Common Differences and Limitations

A calculator’s schedule may not match a lender’s final figures exactly. A lender may calculate interest using specific calendar dates or a daily accrual method, round each period differently, or include financed charges in the principal. The first payment may also fall on a date that creates a shorter or longer initial interest period. The calculator does not account for these details.

Extra payments can change a real schedule, but the calculator does not include them. If a lender applies an extra amount to principal, the balance may be repaid earlier and interest may be reduced, subject to the loan’s terms and how the payment is processed. A schedule generated by the lender is needed to show the effect accurately. Do not assume an extra payment automatically changes the required monthly payment; the lender’s process determines that.

Another common misunderstanding is that the APR and the monthly rate are interchangeable. APR is entered annually as a percentage; this calculation divides it by 12 to get a monthly rate. APR may reflect certain borrowing costs in ways a simple interest-rate calculation does not, so the formula is an estimate rather than a complete reconstruction of every disclosure figure.

Frequently Asked Questions

What is a personal loan repayment schedule?
A repayment schedule lists the payments over the loan term and shows how each payment is allocated to interest and principal, along with the remaining balance.

How do I calculate a personal loan monthly payment?
Use the fixed-payment formula with the principal, monthly rate (APR divided by 1,200) and number of monthly payments. This calculator performs that calculation and rounds the payment to cents.

Why does the interest portion change if my payment stays the same?
Interest is calculated on the outstanding balance. As principal is repaid, the balance declines, so less interest accrues per period and more of a level payment goes toward principal.

Does this calculator include fees or extra payments?
No. It models equal monthly payments on the entered principal at a fixed APR. It does not add fees, model extra principal payments or reproduce a lender’s exact dated schedule.

Why is my lender’s payment different from the estimate?
The principal, APR, term, payment timing, fees, rounding method or interest-accrual method may differ from the inputs or assumptions here. Check the lender’s disclosure for the exact figures.

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 | $ | p * (apr / 1200) / (1 - (1 + apr / 1200) ^ -(yrs * 12)) | 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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