Amortization Calculator
View a full amortization schedule showing principal and interest breakdown.
How it works (Formula)
Calculates the exact amount applied to principal and interest each month for the life of the loan. What Is the Amortization Calculator?
The Amortization Calculator is an essential tool for borrowers who want to see the long-term lifecycle of their loan. While a standard mortgage calculator tells you what your monthly bill is, this tool reveals how much of that check goes to the bank (interest) and how much adds to your ownership (principal) every single month.
What makes the Nuumra version better is our "Extra Payment" feature combined with real-time visual tracking. You can instantly see how adding a small amount to your monthly principal can shave years off your loan and save you tens of thousands in interest charges.
How to Use the Amortization Calculator
- Loan Amount — Enter the total amount you are borrowing from the lender.
- Interest Rate — Enter your annual percentage rate (APR) for the loan.
- Loan Term — Choose the duration of the loan, most commonly 15 or 30 years.
- Extra Monthly Principal — Enter any additional amount you plan to pay each month to see your savings.
- Click Calculate — Press the Generate Schedule button to instantly see your payoff timeline.
How the Amortization Formula Works
Our calculator uses the standard sinking fund and declining balance method:
Monthly Principal = Total Payment − Monthly Interest
- Total Payment — Fixed amount determined by the loan term and rate.
- Remaining Balance — The principal owed at the start of each period.
- Cumulative Interest — The running total of interest paid over the life of the loan.
Example: On a $320,000 loan at 6.5%, your first payment of $2,022.62 consists of $1,733.33 in interest and only $289.29 in principal. Over time, the interest portion shrinks and the principal portion grows.
Understanding Your Amortization Results
Once you hit Calculate, here is what each result means:
- Base Mo. Payment — Your standard monthly principal and interest payment.
- Total Interest Paid — The total profit the lender makes from your loan over the full term.
- Total Cost — The combined total of the principal you borrowed plus all interest payments.
- Payoff Timeline — The exact age of the loan when it reaches a $0 balance, including time saved from extra payments.
Tips to Get the Most Out of the Amortization Calculator
- One Extra Payment — Making just one extra monthly principal payment per year can cut 4-5 years off a 30-year mortgage.
- Identify the Tipping Point — Use the chart to see the year when you finally start paying more principal than interest each month.
- Refinance Strategy — Use this tool to see if you are early in your loan; if so, refinancing to a lower rate has the maximum interest-saving impact.
- Monthly vs. Yearly — Paying extra monthly rather than a lump sum yearly reduces the principal balance faster, saving slightly more interest.