Everyday
Extra Loan Payment Calculator
Estimate how an extra monthly payment changes loan payoff time and total interest.
- Free to use
- Runs in your browser
- Level A · Standard formula
- Last reviewed 2026-08-16
Calculator guide
How to use the Extra Loan Payment Calculator
Estimate how an extra monthly payment changes loan payoff time and total interest. Enter the requested values and select Calculate. The result and supporting values are produced locally in your browser.
Formula
Worked example
Adding $200 per month to a fixed-rate amortizing loan can shorten the payoff period and reduce total interest.
What to keep in mind
- This assumes the extra amount is applied to principal every month without prepayment penalties.
- Actual lender timing, daily interest, fees, escrow, and rounding practices can change results.
Methodology
This calculator uses deterministic arithmetic and performs the calculation locally in your browser. Verify assumptions, units, and source values for your specific use case.
Review standard: Level A · Standard formula. How calculator reviews work.
Frequently asked questions
What does this calculator calculate?
Estimate how an extra monthly payment changes loan payoff time and total interest.
How is the result calculated?
Simulate monthly amortization using Regular Payment + Extra Payment until balance reaches zero.
Can I use the result for an important decision?
Use the result as a calculation aid and verify the inputs, assumptions, and applicable professional or regulatory requirements before relying on it for an important decision.
Does CalculateMeasure store the values I enter?
The calculator performs its arithmetic in your browser. The calculator itself does not need to send your entered values to a server to produce the result.