Loan Calculator

Calculate your loan payment — see total interest and payoff date.

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How to Use This Calculator

Enter your loan amount and interest rate. The calculator instantly shows your payment amount, total interest, total cost, and payoff date.

Need to adjust the term or payment schedule? Expand "More options" to change the loan term (1–30 years) or switch between monthly and biweekly payments. Biweekly payments result in 26 payments per year instead of 12 — you'll pay off the loan faster and save on interest.

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Every input is encoded in the URL. Click Share, send the link — they'll see your exact numbers. No re-entering, no screenshots.

The Formula

The payment is calculated using the standard annuity formula:

M = P × [r(1 + r)n] ÷ [(1 + r)n − 1]

Where:

For monthly payments, r = annual rate ÷ 12 and n = years × 12. For biweekly, r = annual rate ÷ 26 and n = years × 26.

Total interest = (M × n) − P. This is the true cost of borrowing — the amount you pay above the original loan.

Example

Alex — financing a used car

Alex is buying a used car for $18,000. The dealer offers 6.5% APR over 5 years with monthly payments.

Loan amount$18,000
Interest rate6.5%
Loan term5 years
Monthly payment$352.19
Total interest$3,131
Total paid$21,131

Alex then checks: what if he shortens the term to 3 years?

3-year monthly payment$551.68
3-year total interest$1,861
Savings vs 5-year$1,271 less interest

Higher monthly payment, but $1,271 saved. Alex chose the 3-year term — the extra $199/month was worth it to be debt-free sooner and pay less overall.

FAQ

The interest rate is the cost of borrowing the principal. APR (Annual Percentage Rate) includes the interest rate plus fees and other costs. For this calculator, enter the APR if your lender provides one — it gives a more accurate picture of your true cost.
With a shorter term, you make fewer payments and your balance decreases faster, so there's less principal for interest to accumulate on. A $25,000 loan at 6% costs $3,999 in interest over 5 years, but $8,306 over 10 years — more than double, for the same loan amount and rate.
With biweekly payments, you make 26 half-payments per year instead of 12 full payments. That's equivalent to 13 monthly payments instead of 12 — one extra payment per year. This reduces your principal faster and saves interest over the life of the loan.
No — this calculates principal and interest only. For auto loans, you may also have sales tax (usually rolled into the loan amount). For personal loans, there are typically no additional costs beyond what's included in the APR. If your loan has fees, add them to the loan amount for a more realistic estimate.
Yes — this works for car loans, personal loans, student loans, business loans, or any fixed-rate amortizing loan. It uses the standard annuity formula that applies to all fixed-rate loans with regular payments. For mortgages, try our dedicated mortgage calculator which also factors in property tax, insurance, and PMI.

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