Personal, auto & student loan payments.
Personal, auto & student loan payments.
Enter the total loan amount, the annual interest rate, and the repayment term in months or years. The calculator instantly shows your fixed monthly payment, the total amount repaid over the life of the loan, and the total interest cost. Use this for personal loans, auto loans, student loans, or any fixed-rate installment debt.
The formula behind this calculator is standard amortization โ each payment is the same size, but the interest/principal split shifts each month. Early payments are mostly interest; later ones are mostly principal. Understanding this helps you see why paying off loans early โ or refinancing at a lower rate โ saves so much money.
Three variables determine your payment: loan amount, interest rate, and term. Of the three, interest rate has the largest long-run effect on total cost, while term length has the largest effect on monthly affordability. A longer term lowers your payment but dramatically increases total interest paid.
Example: A $20,000 personal loan at 12% interest over 3 years costs $664/month and $3,900 total interest. Extend that to 5 years and the payment drops to $445/month โ but total interest jumps to $6,700. You pay $2,800 more for the same loan simply by taking longer to repay.
The type of loan matters for the rate you'll get:
The most powerful lever is your credit score โ improving it before applying for any major loan is almost always worth the wait. Going from a 650 to a 720 credit score might drop your personal loan rate from 18% to 11%, saving thousands on a $15,000 loan. Other strategies: make biweekly payments instead of monthly (effectively making one extra payment per year), pay even $25โ$50 extra per month, or refinance if rates have dropped since you borrowed.
Each fixed payment covers the interest accrued since the last one, with whatever remains reducing the principal. Because interest is charged on a shrinking balance, the split between interest and principal changes with every payment — even though the payment itself never moves.
Early payments are mostly interest. On a $20,000 loan at 8% over five years, the first payment of about $406 includes roughly $133 of interest. By the final payment, interest is under $3. The crossover comes surprisingly late on longer terms.
Payment = P × [ r(1+r)n ] ÷ [ (1+r)n − 1 ]
The interest rate is the cost of borrowing the money. The APR includes lender fees, so it reflects what the loan actually costs you.
Comparing a headline rate against an APR is not a like-for-like comparison. A 6.5% rate with a 3% origination fee can be more expensive than a 7.2% rate with none. Lenders are generally required to disclose APR precisely so that borrowers can compare on a consistent basis — it is worth using.
Also check for prepayment penalties. A loan that charges for early repayment removes your ability to reduce total interest by paying ahead, which can matter more than a small rate difference.
Extending a term lowers the monthly payment and raises total interest, often substantially. The same $20,000 at 8% costs about $4,332 in interest over five years and $8,076 over ten — nearly double, for a payment that is only $164 lower.
That trade can be the right call when cash flow is genuinely tight. It is worth making it consciously rather than defaulting to whichever term produces the payment you were quoted.
In the other direction, extra payments go entirely to principal and remove every future interest charge that principal would have generated. Instruct your lender in writing to apply overpayments to principal — left unspecified, many will simply credit next month's instalment, which achieves very little.
The interest rate is the base cost of borrowing. APR (Annual Percentage Rate) includes the interest rate plus fees, origination charges, and other costs โ it's the true annual cost of the loan. Always compare APR when shopping loans, not just the stated rate.
Some lenders charge prepayment penalties โ typically 1โ3% of the remaining balance โ if you pay off early. Always check your loan agreement before making extra payments. Most personal and student loans have no prepayment penalty.
Lenders generally want your total monthly debt payments (including this new loan) to be under 36% of your gross monthly income. Above 43% significantly reduces your chances of loan approval. Use this calculator to check if the monthly payment fits within that range before applying.