Amortization Schedule Calculator
See the full month-by-month breakdown of any loan — what you pay, what goes to interest, and what you still owe.
Full amortisation schedule
| Month | Payment | Interest | Principal | Balance |
|---|---|---|---|---|
| 1 | $2,212.24 | $1,895.83 | $316.40 | $349,683.60 |
| 2 | $2,212.24 | $1,894.12 | $318.12 | $349,365.48 |
| 3 | $2,212.24 | $1,892.40 | $319.84 | $349,045.63 |
| 4 | $2,212.24 | $1,890.66 | $321.57 | $348,724.06 |
| 5 | $2,212.24 | $1,888.92 | $323.32 | $348,400.74 |
| 6 | $2,212.24 | $1,887.17 | $325.07 | $348,075.68 |
| 7 | $2,212.24 | $1,885.41 | $326.83 | $347,748.85 |
| 8 | $2,212.24 | $1,883.64 | $328.60 | $347,420.25 |
| 9 | $2,212.24 | $1,881.86 | $330.38 | $347,089.87 |
| 10 | $2,212.24 | $1,880.07 | $332.17 | $346,757.70 |
| 11 | $2,212.24 | $1,878.27 | $333.97 | $346,423.74 |
| 12 | $2,212.24 | $1,876.46 | $335.78 | $346,087.96 |
Early payments are mostly interest. The crossover — where more of each payment goes to principal than to interest — is the row worth finding.
How this is calculated
Payment = principal × r ÷ (1 − (1 + r)^−n), where r is the monthly rate and n the number of months. Each month, interest is charged on the remaining balance and the rest of the payment reduces it.
An amortizing loan is one where every payment is the same size, but what that payment does changes every single month.
The payment itself comes from the annuity formula: payment = principal × r ÷ (1 − (1 + r)^−n), where r is the monthly interest rate (the annual rate divided by twelve) and n is the number of months. That formula finds the one fixed amount that will clear the balance exactly on schedule.
What happens inside each payment is where the schedule matters. Interest is charged on whatever you still owe, so in month one of a 30-year mortgage at 6.5%, interest takes the overwhelming majority of the payment and only a small slice reduces the balance. Because the balance barely moved, month two is almost identical. The split shifts slowly at first and then accelerates, and the crossover point — the month where more of your payment goes to principal than to interest — usually falls somewhere near the halfway mark on a 30-year term, not at the beginning.
This front-loading is not a fee or a trick. It is arithmetic: you owe the most at the start, so you are charged the most at the start. But it has two practical consequences worth understanding.
The first is that selling or refinancing early means you have built far less equity than the elapsed time suggests. Five years into a 30-year loan you have paid roughly a sixth of the payments and cleared far less than a sixth of the balance.
The second is that an extra payment made early is worth far more than the same payment made later, because it removes principal that would otherwise have accrued interest for the entire remaining term. A single extra payment in year one of a 30-year loan can shorten the term by several months; the same payment in year 25 does very little.
Worked examples
A standard 30-year mortgage
$350,000 borrowed at 6.5% over 30 years.
You repay well over $790,000 on a $350,000 loan — more is paid in interest than was ever borrowed. In month one, roughly $1,896 of the payment is interest and only about $316 reduces the balance.
Load this scenario into the calculatorThe same loan over 15 years
$350,000 at 6.5%, but on a 15-year term instead of 30.
The monthly payment rises by roughly 38%, but total interest falls by around two thirds. Halving the term does not double the payment, because you stop paying interest on a large balance for fifteen extra years.
Load this scenario into the calculatorA car loan
$28,000 at 7.9% over 5 years.
On a short term the front-loading is much milder — the crossover comes within the first year. Short loans are dominated by principal, which is why the total interest stays modest even at a high rate.
Load this scenario into the calculatorWhat this assumes
- The interest rate is fixed for the whole term. Adjustable-rate loans will diverge from this schedule once the rate resets.
- Interest is compounded monthly, which is standard for US and UK mortgages and most instalment loans.
- Payments are made in full and on time, with no missed or partial payments.
- The figures cover principal and interest only. Property taxes, insurance, HOA fees, and PMI are not included and often add substantially to a real mortgage payment.
- No origination fees, points, or closing costs are included, so this is not the same as an APR comparison.
Common questions
- Why is almost all of my early payment going to interest?
- Because interest is charged on the balance you still owe, and at the start you owe nearly the whole loan. The payment is fixed, so once the interest is taken, only what's left reduces the principal. As the balance falls, the interest portion falls with it and the principal portion grows.
- When does more of my payment go to principal than interest?
- On a 30-year loan at typical rates, roughly halfway through the term — around year 17 to 19 at 6.5%. Higher rates push the crossover later; shorter terms bring it much earlier. Find the row in the schedule above where the two columns swap over.
- Does this include taxes and insurance?
- No. This shows principal and interest only. A real mortgage payment usually also includes property tax, homeowner's insurance, and sometimes PMI or HOA fees held in escrow, which can add several hundred dollars a month on top of the figure here.
- Why does my lender's number differ slightly from this one?
- Usually rounding or day-count conventions. Some lenders compute interest daily rather than monthly, and some round each payment to the nearest cent in a slightly different way. Differences of a few dollars over the life of a loan are normal; differences of hundreds usually mean fees are bundled into their figure.
- Is it better to take a longer term and invest the difference?
- It depends entirely on the rate you are paying versus the return you would earn, after tax. Paying down a 7% loan is a guaranteed 7% return; a market investment is neither guaranteed nor tax-free. At low mortgage rates the argument for investing is strong, and at high rates it weakens considerably.
Related calculators
- Extra Mortgage Payment Calculator — See exactly how much interest an extra monthly payment saves, and how many years it takes off your mortgage.
- Biweekly Mortgage Payment Calculator — Compare paying half your mortgage every two weeks against paying monthly, and see what the switch actually saves.
- Auto Loan Early Payoff Calculator — See what paying extra on your car loan saves in interest, and how much sooner you own the car outright.