CALTRX

Loan Calculator

Calculate your monthly loan payment, total interest, and see a complete amortization breakdown for any fixed-rate loan.

M = P × r(1+r)^n / [(1+r)^n − 1]
M= Monthly payment
P= Principal (loan amount)
r= Monthly interest rate (annual rate / 12)
n= Total number of payments (years × 12)

Tips & Notes

  • ✓Compare total interest paid, not just monthly payments, when evaluating loan offers.
  • ✓Making even small extra principal payments early in the loan term can save significant interest.
  • ✓A shorter loan term means higher monthly payments but substantially less total interest.
  • ✓Check for prepayment penalties before making extra payments on any loan.

Common Mistakes

  • ✗Focusing only on monthly payment amount while ignoring total interest cost.
  • ✗Not accounting for fees and origination charges when comparing loan offers.
  • ✗Confusing APR with the nominal interest rate—APR includes fees and gives the true cost.
  • ✗Extending the loan term to get a lower payment without realizing the added interest cost.

Loan Calculator Overview

How Loan Payments Work

A fixed-rate loan amortization schedule ensures equal monthly payments throughout the loan term. Each payment is split between interest on the remaining balance and principal reduction. Early payments are interest-heavy; later payments are principal-heavy. The standard amortization formula calculates the fixed monthly payment that will fully repay the loan by the end of the term.

Key Factors Affecting Loan Cost

Three primary variables determine total loan cost: the principal amount, the interest rate, and the loan term. Increasing any of these increases the total cost. A longer term reduces the monthly payment but significantly increases total interest paid. Even small rate differences compound dramatically over time—a 1% rate reduction on a $30,000 loan over 5 years saves over $800 in interest.

Practical Applications

This calculator serves anyone evaluating borrowing options: comparing personal loan offers from different lenders, deciding between loan terms, assessing the benefit of a larger down payment to reduce the loan amount, or determining whether refinancing at a lower rate makes financial sense after accounting for any fees involved.

Frequently Asked Questions

The standard amortization formula M = P × r(1+r)^n / [(1+r)^n − 1] calculates a fixed monthly payment where P is the loan amount, r is the monthly interest rate, and n is the total number of payments.

Each payment covers interest on the remaining balance first. Since the balance is highest at the start, more of each early payment goes to interest. As the balance decreases, more goes to principal.

Extra payments reduce the principal faster, which reduces future interest charges. Even $50-$100 extra per month can shorten a loan by months or years and save hundreds to thousands in interest.

The interest rate is the cost of borrowing the principal. APR includes the interest rate plus fees and other costs, giving a more complete picture of the total borrowing cost.