Amortization Schedule Calculator
Use this free amortization schedule calculator to generate a complete month-by-month loan table. See how each payment splits between principal and interest, your total interest, and your payoff date — with optional extra payments and CSV export.
| Month | Payment | Principal | Interest | Balance |
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How to Use This Amortization Schedule Calculator
- Loan Amount — the principal borrowed.
- Annual Interest Rate — the loan's yearly rate.
- Term — repayment period in years.
- Extra Monthly Payment — optional; see how extra payments cut interest and shorten the term.
What Is an Amortization Schedule?
An amortization schedule is a complete, month-by-month table of every payment on a loan, showing exactly how each one is split between principal and interest, and how the balance declines to zero. It turns a single monthly payment figure into the full story of what a loan really costs over its life.
The key insight an amortization schedule reveals is front-loaded interest: in the early months, most of each payment goes to interest and very little to principal. As the balance falls, the split gradually reverses. This is why making extra principal payments early has an outsized effect — it removes future interest on that principal for the entire remaining term. Seeing the full schedule helps you understand refinancing decisions, the true cost of a longer term, and the payoff impact of paying ahead.
Amortization Formula
Monthly Payment = P × r ÷ (1 − (1 + r)^−n)Each month:
Interest = Balance × r, Principal = Payment − Interest
Example Calculation
A $250,000 loan at 7% over 15 years (180 months):
- Monthly payment ≈ $2,247
- Total interest over the life ≈ $154,538
- Total paid ≈ $404,538
Adding extra to each payment can shave years and tens of thousands in interest off the total — try it above.
Common Mistakes to Avoid
- Looking only at the monthly payment. The total interest over the term is the number that reveals the real cost.
- Underestimating early interest. Early payments are mostly interest — paying extra early saves the most.
- Ignoring prepayment penalties. Some loans charge for paying ahead; confirm before planning extra payments.
- Forgetting fees and insurance. The schedule shows principal and interest only, not escrow, fees, or insurance.
Amortization for Small Business
Whether it is a term loan, equipment financing, or commercial real estate, understanding amortization helps you compare financing offers on true total cost, plan cash flow around the payment, and decide whether extra payments or refinancing make sense. The headline rate alone never tells the full story — the schedule does.
If you are structuring new debt, weighing a refinance, or trying to pay down existing loans efficiently, our fractional CFOs can model the options against your cash flow. A free call can quickly show you the smartest path.
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