An amortization schedule shows how each loan payment splits between principal and interest over time. Use this calculator to plan mortgages, auto loans, personal loans, or business debt with a clear view of total borrowing cost.
How to use this calculator
- Enter the original loan amount (principal).
- Enter the annual interest rate as a percentage.
- Set the loan term in years.
- Choose how often payments are made (monthly, biweekly, quarterly, or annually).
- Review the periodic payment, total interest, amortization table, and decision insights.
Formula
Periodic payment = P × [r(1+r)^n] / [(1+r)^n − 1], where P is loan amount, r is the periodic interest rate, and n is the total number of payments. Each period, interest is calculated on the remaining balance and the rest of the payment reduces principal.
Example
A $250,000 loan at 6.5% over 30 years with monthly payments costs about $1,580 per month and roughly $318,000 in total interest over the full term.
Frequently asked questions
What is a loan amortization schedule?
It is a table listing each payment period with the payment amount, principal portion, interest portion, and remaining balance until the loan is paid off.
Why is more interest paid early in the loan?
Interest is calculated on the remaining balance. When the balance is highest at the start, interest charges are larger even though the payment stays the same.
Does biweekly payment frequency shorten my loan?
Biweekly schedules use 26 payments per year, which can retire principal faster than 12 monthly payments. This calculator models equal periodic payments at your selected frequency.
Can I see how extra payments affect interest?
This version models the standard schedule. The early payoff insight illustrates approximate interest savings from a shorter term — use it as a starting point for prepayment planning.