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Results will appear here
Results
Original Time to Payoff
months
New Time to Payoff
months
Time Saved
months
Interest Saved
About Loan Payoff Calculator
Calculation Method
This calculator determines how much sooner you can pay off your loan and how much interest you can save by comparing your original payment schedule with a new schedule that includes extra payments. It uses the amortization formula to calculate the interest and principal allocation for each month.
Formula
The number of remaining months N is calculated using the following formula (derived from the amortization formula):
N = -log(1 - (r × B) / P) / log(1 + r)
- N = Number of Remaining Months
- B = Current Loan Balance
- r = Monthly Interest Rate (Annual Rate / 12)
- P = Monthly Payment (Original + Extra)
