Loan Calculator
Monthly payment, total interest and a year-by-year schedule for a fixed-rate loan, with optional extra payments.
Your loan
Filled in with example values. Replace them with your own.
Optional
An extra amount on top of the regular payment, applied to the balance.
Currency symbol
Results update as you type.
Result
Loan $20,000.00 at 6% over 5 years: $386.66 a month, $3,199.35 interest, $23,199.35 in total
Monthly payment
$386.66a month
- Total interest
- $3,199.35
- Total paidLoan + interest
- $23,199.35
- Paid off in
- 5 years
- Final paymentClears the last of the balance
- $386.41
What you repay
- Amount borrowed
- $20,000.00
- Interest
- $3,199.35
- Total repaid
- $23,199.35
Year by year
| Year | Interest | Principal | Balance |
|---|---|---|---|
| 1 | $1,103.81 | $3,536.11 | $16,463.89 |
| 2 | $885.72 | $3,754.20 | $12,709.69 |
| 3 | $654.16 | $3,985.76 | $8,723.93 |
| 4 | $408.33 | $4,231.59 | $4,492.34 |
| 5 | $147.33 | $4,492.34 | $0.00 |
How it’s calculated
Monthly rate
6% ÷ 12 = 0.5%
Payment
P × i ÷ (1 − (1 + i)^−60) = $386.66
Total interest
sum of each month’s interest = $3,199.35
How the loan calculator works
For a fixed-rate loan repaid in equal monthly instalments, the payment is set so that the loan is fully repaid, with interest, by the last month. Each month, interest is charged on the remaining balance and the rest of the payment reduces it.
The calculator works through the loan month by month in whole cents, the way a statement does, so the total interest and the year-by-year table add up exactly. An optional extra payment goes straight to the balance.
The formula
i = Yearly rate ÷ 12
Payment = P × i ÷ (1 − (1 + i)^−n)
Total interest = Total paid − P
P is the amount borrowed and n the number of monthly payments. At 0% the payment is simply P ÷ n.
Worked example
A car loan of 20,000 at 6% a year over 5 years (60 payments):
- Monthly rate: 6% ÷ 12 = 0.5%
- Payment: 20,000 × 0.005 ÷ (1 − 1.005^−60) = 386.66 a month
- Total interest: 3,199.35, so 23,199.35 is repaid in total
Paying an extra 100 a month clears the loan in 47 months instead of 60 and saves 754.99 in interest.
Assumptions and limitations
- The rate is fixed for the whole term and interest is charged monthly on the balance.
- Fees, insurance and taxes are not included.
- Monthly interest is rounded to the cent, half up. Your lender’s statement may differ by a few cents.
Frequently asked questions
Why is most of the early payment interest?
Interest is charged on the balance you still owe. At the start the balance is highest, so more of each payment goes to interest. As the balance falls, the interest part shrinks and more of the payment reduces the loan.
Is the rate I enter the APR?
Enter the yearly interest rate on the loan. The calculator divides it by 12 and charges it monthly. In some countries the quoted APR also includes certain fees, so if your loan has arrangement fees, the true cost can be higher than the interest shown here.
Do extra payments always save money?
They reduce the balance sooner, so less interest builds up. Some loans charge a fee for paying early or only allow overpayments up to a limit, so check your agreement before you rely on the saving shown.
Why is the final payment different?
Payments are rounded to the cent, so the last one is adjusted to clear exactly what is left of the balance.
Can I use this for a mortgage?
For a simple fixed-rate repayment mortgage, yes. It does not include property taxes, insurance, fees, or rate changes on variable or fixed-then-variable deals.