What Is a Loan Calculator?
A loan calculator helps you figure out the monthly payment and total cost of borrowing money. Whether you're considering a personal loan, auto loan, student loan, or any other type of installment credit, understanding the real cost beyond the principal amount is essential for making smart borrowing decisions.
How Amortizing Loans Work
Most consumer loans are amortizing, meaning you make equal monthly payments that cover both principal (the amount you borrowed) and interest (what the lender charges for the loan). Early in the loan term, most of each payment goes toward interest. Over time, more of your payment is applied to the principal balance.
Loan Payment Formula
The monthly payment on a fixed-rate loan follows the standard amortization formula:
Where:
- PMT = monthly payment
- PV = present value (loan amount / principal)
- r = periodic interest rate (annual APR / 12)
- n = total number of payments
Personal Loan Calculator Example
Suppose you borrow $15,000 for a home improvement project at 8.5% APR with a 5-year repayment term. Here is how the numbers break down:
- Loan amount: $15,000
- Annual rate: 8.5% → monthly rate: 0.007083
- Term: 60 months
- Monthly payment: approximately $308
- Total interest paid: approximately $3,480
- Total of all payments: approximately $18,480
Benefits of Extra Payments
Adding even a small amount to your monthly payment can dramatically reduce the total interest you pay and shorten your loan term. Because extra payments go directly toward principal, they save you money by reducing the balance that interest is calculated on.
For example, paying an extra $50 per month on a $15,000 loan at 8.5% over 5 years can save you hundreds of dollars in interest and pay off the loan several months early. Enter an extra payment amount in the calculator above to see the potential savings.
Frequently Asked Questions
What is a good interest rate for a personal loan?
Personal loan rates vary widely based on your credit score, income, and the lender. Borrowers with excellent credit may qualify for rates below 7%, while those with fair credit might see rates of 15-25%. Always compare offers from multiple lenders to find the most competitive rate.
Does prequalification affect my credit score?
Most lenders offer prequalification with a soft credit pull that does not impact your credit score. A formal application, however, triggers a hard inquiry which can temporarily lower your score by a few points. Try to complete all rate shopping within a 14-45 day window to minimize the impact.
Should I pay off my loan early?
Paying off a loan early saves you money on interest, but it is not always the best financial move. If your loan has a low interest rate, you might earn a better return by investing extra money instead. Check whether your loan has a prepayment penalty, and weigh the interest savings against other financial priorities like building an emergency fund or saving for retirement.