Amortization Calculator
See every payment on your loan: how much is interest, how much pays off the loan, and what's left. Add extra payments to see the interest and time you save.
Blank = the 1st of next month.
Most loans: same as payments. Canadian mortgages: half-yearly.
A lump sum still owed with the last payment, as on some car and business loans. It lowers the regular payment.
Extra money goes straight to the balance. Your regular payment stays the same, so the loan ends sooner.
Amortization schedule and chart
How your schedule is worked out
Each payment pays the interest due first; the rest cuts the balance.
- 1
Rate per payment
6% ÷ 12= 0.5%
- 2
The same payment
$200,000 × 0.005÷ (1 − 1.005^−180)= $1,687.71
- 3
First payment split
$1,000.00 interest+ $687.71 principalOwed $199,312
- 4
Total interest
All 180 payments= $303,788− $200,000= $103,788
Read more: the formula, a worked example, extra payments, interest-only and balloon loans
Amortization means paying off a loan with equal payments over a set time. Every payment first covers the interest that built up since the last one; whatever is left pays down the loan. As the balance falls, so does the interest, so each payment pays off a bit more principal than the one before. The schedule above lists every payment so you can see exactly where your money goes.
The formula
payment = loan × rate per payment ÷ (1 − (1 + rate per payment)^−number of payments)
rate per payment = yearly rate ÷ payments a year ÷ 100
interest this payment = balance × rate per payment
principal this payment = payment − interest
new balance = balance − principal − any extra payment
with a balloon B: payment = (loan − B × (1 + rate)^−payments) × rate ÷ (1 − (1 + rate)^−payments)
Worked example
A loan of $200,000 at 6% a year for 15 years, paid monthly, has a rate per payment of 6 ÷ 12 ÷ 100 = 0.005 and 180 payments. (1.005)180 = 2.4541, so the payment is $200,000 × 0.005 × 2.4541 ÷ 1.4541 = $1,687.71.
In month 1 the interest is $200,000 × 0.005 = $1,000.00, so $1,687.71 − $1,000.00 = $687.71 pays off the loan and $199,312.29 is left. In month 2 the interest is a little lower ($996.56), so a little more goes to the loan. Over all 180 payments you pay $303,788.46, of which $103,788.46 is interest. After 60 payments (5 years) you still owe $152,018.20.
Extra payments
Adding $100 to every payment on the same loan clears it in 165 payments instead of 180 and saves $10,028.47 in interest. Paying $2,000 extra once a year instead clears it in 156 payments and saves $14,599.22. Extra money paid early saves the most, because it stops interest building on that amount for every month that follows.
Every 2 weeks and accelerated payments
Spreading the same loan over 26 payments a year ($778.30 every 2 weeks) brings the total interest down only slightly, to $103,536.93. The accelerated kind pays half the monthly payment ($843.86) every 2 weeks. That adds up to 13 monthly payments a year instead of 12, so the loan ends after 344 payments (about 13 years 3 months) and you save $13,941.66 against paying monthly.
Interest-only periods and balloons
With the first 5 years interest-only, you pay $1,000 a month for 60 months while the balance stays at $200,000. The full loan must then be repaid over the last 10 years, so the payment jumps to $2,220.41 and total interest rises to $126,449.20. Leaving a $50,000 balloon at the end instead lowers the monthly payment to $1,515.79, but the final payment is $51,515.79 and total interest is $122,841.34.
Ways to pay less interest
- A shorter term raises the payment but cuts the total interest sharply.
- Small regular extra payments, started early, often save more than one large payment late in the loan.
- Check with your lender that extra payments go to the principal, and whether any early repayment fee applies.
Assumes a fixed interest rate for the whole term and interest worked out per payment period. Your lender's figures may differ by a few cents because of rounding, day-count rules or the date of the first payment. For a quick payment check see the loan calculator; for property tax, insurance and PMI use the mortgage calculator; for Indian-style EMIs with part-payments use the EMI calculator.
Common questions
What is an amortization schedule?
It is a table of every payment on a loan, showing how much of each one goes to interest and how much pays off the loan, plus the balance left afterwards. Each payment is the same, but early on most of it is interest. For 200,000 at 6% over 15 years, the first payment of 1,687.71 is 1,000 of interest and 687.71 of principal.
How is a loan amortization payment worked out?
Payment = loan × rate per payment ÷ (1 − (1 + rate per payment)^−number of payments). The rate per payment is the yearly rate divided by the number of payments a year. 200,000 at 6% for 15 years monthly is 200,000 × 0.005 ÷ (1 − 1.005^−180) = 1,687.71 a month, with 103,788.46 of interest in total.
How much do extra payments save?
Extra money goes straight to the balance, so less interest builds up afterwards and the loan ends sooner. Adding 100 a month to a 200,000 loan at 6% over 15 years pays it off in 165 payments instead of 180 and saves 10,028.47 in interest. Extra payments early in the loan save the most.
Do bi-weekly payments pay off a loan faster?
Plain payments every 2 weeks (the same loan spread over 26 payments a year) save only a little. The "accelerated" kind, half the monthly payment every 2 weeks, adds up to 13 monthly payments a year. On 200,000 at 6% over 15 years that is 843.86 every 2 weeks, clearing the loan in about 13 years 3 months and saving 13,941.66 in interest.
How does an interest-only period change the schedule?
During the interest-only period you pay just the interest, so the balance does not fall. Afterwards the whole loan must be repaid in the years left, so payments jump. 200,000 at 6% over 15 years with 5 years interest-only is 1,000 a month, then 2,220.41 a month for 10 years, and total interest rises to 126,449.20.
Can I download or print my amortization schedule?
Yes. Use "Download CSV" under the schedule to get every payment (or the yearly totals) as a file that opens in Excel, Google Sheets or Numbers. "Print schedule" opens a clean printable sheet with your loan details and the full table, which you can also save as a PDF from the print window.
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