See How Extra Payments Affect Your Loan
Calculation Methodology
Monthly Payment Formula
Monthly car loan payments are calculated using a standard amortization formula commonly used in banking:
M = P × [r(1+r)^n] / [(1+r)^n – 1]
- M: Monthly payment amount
- P: Loan principal (total borrowed amount)
- r: Monthly interest rate (annual APR ÷ 12)
- n: Total number of payments over the loan term
How Interest Is Calculated
Each payment cycle is split between interest and principal repayment:
- Interest = Remaining loan balance × monthly interest rate
- Principal = Monthly payment − interest portion
- New balance = Previous balance − principal paid
Effect of Extra Payments
Making additional payments directly reduces the loan principal. This lowers future interest charges and helps shorten the overall loan term, saving money over time.
Lump Sum Payments
A one-time lump sum payment is applied entirely to the principal. This immediately reduces the remaining balance and decreases the total interest paid over the life of the loan.
Reference Sources
- Standard loan amortization principles
- Consumer Financial Protection Bureau (CFPB) guidance
- Federal Reserve lending and interest calculation standards
Disclaimer
This calculator provides estimated results only. Actual loan terms, interest charges, and repayment amounts may vary depending on lender policies, credit profile, and additional fees. Always confirm final details with your lender.