See how making extra payments influences your loan
Calculation Methodology
Monthly Payment Formula
Monthly payments are determined via the standard loan amortization formula:
M = P × [r(1+r)^n] / [(1+r)^n – 1]
- M: Monthly installment
- P: Principal amount
- r: Monthly rate (APR divided by 12)
- n: Total payment count
Interest Calculation
During each cycle:
Interest = Outstanding Balance × Monthly Rate
Principal = Payment – Interest Portion
Next Balance = Current Balance – Principal
Prepayment Impact
Extra payments go straight toward principal, reducing interest moving forward. Over time this accelerates loan payoff and decreases the overall interest paid.
Lump Sum Payment
A single lump sum contribution is entirely applied to principal, providing an immediate reduction in future interest calculations.
References
- Financial Mathematics Amortization Rules
- CFPB Loan Explanation Materials
- Federal Reserve Lending Guidelines
Disclaimer: This calculator provides estimated values. Actual loan terms may differ due to lender policies and additional charges. Check with your lender for precise details.