Loan & Debt Payoff Calculator: Strategies & Amortization
Model multiple loans, extra payments, step-ups, and lump sums to see how fast you can be debt-free and how much interest you save. Home, car, personal, and student loans alike.
Frequently asked questions
How does the loan calculator work?
Enter each loan’s amount, APR, and term in years. The standard monthly amortization formula gives the required payment, the total interest over the full term, and the total paid. All loan math runs locally in your browser.
What difference does an extra monthly payment make?
The extra amount is added to your payment each month and hits the balance directly after that month’s interest accrues. The simulator runs the schedule month by month and shows the earlier payoff date, the months you cut, and the interest dollars saved.
Avalanche or snowball: which order should I pay loans?
Snowball clears the smallest balance first for momentum; avalanche targets the highest APR first and always costs less interest. The scenario planner here uses avalanche: every loan receives its required minimum, and all extra money goes to the highest-rate loan first.
What other levers cut the total interest?
On top of a flat extra payment you can add an annual step-up that raises your total monthly outlay by a percentage each year, and a yearly lump sum (a bonus or refund) that goes straight at the highest-rate loan. The balance timeline shows how much faster each plan finishes.