What is my amortization schedule?
See every payment of a fixed-rate loan, split into principal and interest, and what extra payments save.
- Monthly payment
- $1,580.17
A $250,000.00 loan at 6.5% is repaid with $1,580.17 a month; with the payments shown it takes 360 payments and $318,861.22 of interest.
- Loan amount
- $250,000.00
- Total interest
- $318,861.22
- Total of payments
- $568,861.22
- Number of payments
- 360
- Paid off in
- September 2056
- Months
- 360
Answer for the example date Tuesday, September 29, 2026. It changes to today's date when the page loads.
Monthly payment: $1,580.17. A $250,000.00 loan at 6.5% is repaid with $1,580.17 a month; with the payments shown it takes 360 payments and $318,861.22 of interest.
How much of what you repay is interest?
How fast does the balance fall?
Where does each year of payments go?
What does every payment look like?
The results are estimates for information only. They are not financial, tax, or legal advice. Check the numbers with your lender or a qualified professional before you decide. Terms of use
How to calculate
Computes the monthly payment and the payment-by-payment amortization schedule of a fixed-rate loan, with optional extra monthly, yearly, and one-time payments.
Example with the default inputs (Loan amount $250,000.00, Interest rate (APR) 6.5%, Loan term (years) 30, Plus months 0, Loan start date September 29, 2026, Extra each month $0.00, Extra each year $0.00, One-time extra payment $0.00, With payment number 12) on the example date Tuesday, September 29, 2026: A $250,000.00 loan at 6.5% is repaid with $1,580.17 a month; with the payments shown it takes 360 payments and $318,861.22 of interest.
Method: payment = L × r ÷ (1 − (1 + r)^−n), with L the loan amount, r the APR ÷ 12, and n the number of months; each month, interest = balance × r, and the payment plus any extra, minus the interest, lowers the balance.
- The rate is fixed and interest is charged monthly at APR ÷ 12 on the balance.
- Payments are made at the end of each month, starting one month after the start date.
- Extra payments go straight to the balance; the yearly extra is paid with payments 12, 24, 36, and so on.
- The last payment is whatever is left, so the principal parts add up to the loan amount.
- Values are not rounded to the cent between months; only the display is rounded.
Worked examples
Each example is checked against the calculator on every build.
- Loan amount $200,000.00, Interest rate (APR) 6%, Loan term (years) 30 gives Monthly payment $1,199.10, Total interest $231,676.38, Number of payments 360.Source: hand calculation in content.mdx; Python 3 cross-check in docs/progress/WP-31/python/amortization.py
- Loan amount $10,000.00, Interest rate (APR) 0%, Loan term (years) 1, Plus months 6, Loan start date 2026-10-15 gives Monthly payment $555.56, Total interest $0.00, Number of payments 18, Paid off in 2028-04-15.Source: hand calculation in content.mdx: 10,000 ÷ 18
- Loan amount $200,000.00, Interest rate (APR) 6%, Loan term (years) 30, Extra each month $200.00 gives Number of payments 252, Total interest $151,875.87, Interest saved by paying extra $79,800.51, Months saved by paying extra 108.Source: hand calculation in content.mdx, month by month in Python (docs/progress/WP-31/python/amortization.py)
- Loan amount $100,000.00, Interest rate (APR) 5%, Loan term (years) 15, Extra each year $1,000.00, One-time extra payment $10,000.00, With payment number 24 gives Monthly payment $790.79, Number of payments 138, Total interest $29,822.43.Source: month by month in Python (docs/progress/WP-31/python/amortization.py), rule in content.mdx
How it works
The monthly payment is the level payment that repays the loan over its term:
payment = L × r ÷ (1 − (1 + r)^−n)
- L is the loan amount.
- r is the monthly rate: the APR divided by 12, as a decimal (6% gives r = 0.005).
- n is the number of monthly payments: years × 12 plus the extra months.
- At 0% the payment is L ÷ n.
Then the schedule runs month by month, for payment number k = 1, 2, 3, …:
- interest = balance × r
- extra = the extra monthly amount, plus the extra yearly amount when k is a multiple of 12 (payments 12, 24, 36, …), plus the one-time amount when k is the payment number you chose (payment 12 when that box is empty).
- If k = n, or payment + extra − interest is at least the balance, this is the last payment: it pays the whole balance plus the interest, and the balance becomes 0.
- Otherwise principal = payment + extra − interest, and the new balance is the balance minus the principal.
Totals:
- Total interest is the sum of the monthly interest.
- Total of payments is the loan amount plus the total interest.
- Without extra payments the interest is n × payment − L. "Interest saved" is that figure minus the interest with the extra payments, and "Months saved" is n minus the number of payments. Both show only when an extra payment is actually made: an extra amount due on a payment before payment n. (Payment n pays whatever is left, so an extra due on it changes nothing.) Without such an extra, total interest is exactly n × payment − L.
- The first payment is one month after the start date. "Paid off in" is the month of the last payment. Without a start date the rows are numbered only.
Assumptions
- The rate is fixed for the whole loan.
- Interest is charged monthly at APR ÷ 12 on the balance, and payments are made at the end of each month.
- Extra payments go straight to the balance and do not change the level payment.
- Values are not rounded to the cent between months; only the display is rounded. A lender's schedule, which rounds each payment to the cent, can differ by a few cents.
Worked examples by hand
$200,000 at 6% over 30 years. r = 0.06 ÷ 12 = 0.005 and n = 360. (1.005)^−360 = 0.166042, so the payment is 200,000 × 0.005 ÷ (1 − 0.166042) = $1,199.10. The interest is 360 × 1,199.101 − 200,000 = $231,676.38. The first month's interest is 200,000 × 0.005 = $1,000, so the first payment lowers the balance by only $199.10.
$10,000 at 0% over 1 year and 6 months, starting October 15, 2026. n = 18, so the payment is 10,000 ÷ 18 = $555.56 with no interest. The last payment is 18 months after the start: April 2028.
The first loan with $200 extra each month. Each month pays $1,399.10 against the balance. Running the monthly rule, the balance runs out at payment 252, so the loan ends 108 months sooner. The interest adds up to $151,875.87, which is $79,800.51 less than $231,676.38.
$100,000 at 5% over 15 years, with $1,000 extra each year and $10,000 extra with payment 24. r = 0.05 ÷ 12 and (1 + r)^−180 = 0.473103, so the payment is 100,000 × 0.0041667 ÷ (1 − 0.473103) = $790.79. Payments 12, 24, 36, … carry $1,000 more, and payment 24 also carries $10,000. Running the monthly rule, the loan ends at payment 138 with $29,822.43 of interest.
Other questions people ask
What is an amortization schedule?
It is a table of every payment on a loan. Each row shows how much of the payment pays interest, how much lowers the balance (principal), and the balance left after the payment. The schedule above shows it by year or by month.
Why is most of my early payment interest?
Interest each month is the balance times the monthly rate. At the start the balance is at its highest, so the interest is too, and only a small part of the level payment is left to lower the balance. As the balance falls, the interest falls and more of the same payment goes to principal. On a $200,000 loan at 6% over 30 years, the first payment of $1,199.10 is $1,000 of interest and $199.10 of principal.
How do extra payments change the schedule?
An extra payment goes straight to the balance. A lower balance means less interest next month, so more of every later payment goes to principal and the loan ends sooner. Paying $200 more each month on a $200,000 loan at 6% over 30 years ends it after 252 payments instead of 360 and saves $79,800.51 of interest.
Does an extra payment lower my monthly payment?
No. On a normal fixed-rate loan the payment stays the same and the loan ends sooner. Some lenders will recalculate a lower payment after a large extra payment (a recast); see the mortgage recast calculator for that case.
Is the monthly rate the APR divided by 12?
For most US mortgages and auto loans, yes: interest is charged monthly at the yearly rate divided by 12. This page uses that rule. A loan that compounds on a different schedule has a slightly different payment; the loan calculator lets you pick the compounding.
Can a lender charge me for paying early?
Some loans have a prepayment penalty, a fee for paying off all or part of the loan early. The CFPB notes that it does not normally apply to small extra principal payments, but check your loan papers before you pay a large amount.