Amortization Schedule Calculator

How to Use This Tool

Follow these simple steps to generate a complete amortization schedule for your loan:

1. Enter your total loan amount (principal) in dollars.
2. Input the annual interest rate offered by your lender as a percentage.
3. Specify the loan term in years (e.g., 30 for a standard mortgage).
4. Select your payment frequency from the dropdown (monthly, bi-weekly, or weekly).
5. Click the "Calculate Schedule" button to view your full payment breakdown.
6. Use the "Reset" button to clear all fields and start over, or "Copy Results" to save your summary.

Formula and Logic

The calculator uses the standard fixed-rate amortization formula to compute periodic payments and schedule breakdowns:

• Periodic Interest Rate = (Annual Interest Rate / 100) / Payments Per Year
• Number of Payments = Loan Term (Years) * Payments Per Year
• Periodic Payment = (Loan Amount * Periodic Rate * (1 + Periodic Rate)^Number of Payments) / ((1 + Periodic Rate)^Number of Payments - 1)

For each payment period, we calculate the interest portion as the remaining balance multiplied by the periodic rate, the principal portion as the periodic payment minus the interest portion, and update the remaining balance by subtracting the principal portion. Total interest is the sum of all interest portions across the full loan term.

Practical Notes

Keep these finance-specific factors in mind when using your amortization schedule:

• Interest rates are typically compounded at the same frequency as your payment schedule for standard loans.
• Bi-weekly payments can reduce your loan term by several years and save significant interest compared to monthly payments.
• Extra principal payments (not included in this calculator) can further shorten your loan term and reduce total interest.
• Always confirm your lender's exact terms, as some loans may have prepayment penalties or variable rates.
• Amortization schedules assume consistent, on-time payments for the full loan term.

Why This Tool Is Useful

This calculator helps you make informed financial decisions before committing to a loan:

• Compare total interest costs across different loan terms (e.g., 15-year vs. 30-year mortgage).
• Plan your monthly budget by knowing exactly how much you need to pay per period.
• Understand how much of each payment goes toward interest vs. principal over time.
• Evaluate the impact of different payment frequencies on your total loan cost.
• Share clear payment breakdowns with financial planners or co-borrowers.

Frequently Asked Questions

Does this calculator account for extra principal payments?

No, this tool calculates schedules for fixed periodic payments with no extra contributions. You can manually adjust your principal balance in the schedule to estimate the impact of extra payments.

Why is my first payment mostly interest?

Early in the loan term, the remaining balance is highest, so the interest portion of each payment is larger. As you pay down the principal, the interest portion decreases and the principal portion increases.

Can I use this for adjustable-rate loans?

No, this calculator is designed for fixed-rate loans only. Adjustable-rate loans have changing interest rates, so their schedules cannot be calculated with a single fixed rate input.

Additional Guidance

To get the most accurate results, gather the following documents before using the tool:

• Loan estimate or commitment letter from your lender with exact interest rate and term.
• Any fees rolled into the loan amount (add these to the principal input).
• Confirmation of payment frequency options accepted by your lender.

Remember that this schedule is an estimate, and actual payments may vary slightly due to rounding or lender-specific processing rules. Always verify final payment amounts with your loan officer before budgeting.