Money
Loan Calculator
Monthly payment, total interest and a full amortization schedule for any fixed-rate loan — personal, auto or student. Add an extra monthly payment to see exactly what it saves.
Monthly payment
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total interest
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total paid
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payoff time
Remaining balance over time.
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Frequently asked questions
What is the monthly payment on a $20,000 loan for 5 years?
At 8% APR it is about $405.53 per month, and you pay roughly $4,332 of interest over the 5 years. Enter your own rate above — the payment moves about $10/month for each percentage point of rate at this size.
What is the difference between interest rate and APR?
The interest rate is the cost of borrowing the principal. APR adds mandatory fees (origination, processing) and spreads them over the term, so it is the better number for comparing offers. This calculator uses the rate you enter as a nominal annual rate compounded monthly.
How is loan interest calculated each month?
Each month, interest = remaining balance × (annual rate ÷ 12). The rest of your fixed payment reduces the balance. Early payments are mostly interest; late payments are mostly principal — that shift is what the amortization schedule shows.
Does paying a loan off early save interest?
Yes — every extra dollar of principal stops accruing interest immediately. Use the “extra monthly payment” field to see the exact interest saved and how many months earlier you finish. Check your agreement for prepayment penalties first; most personal and auto loans in the US have none.
What is the difference between simple and compound interest on a loan?
Most installment loans use amortized (compound-style) interest: each month’s interest is computed on the current balance. Simple-interest loans compute interest daily on the balance — in practice the math is nearly identical if you pay on schedule.
Method: standard fixed-rate amortization — monthly interest = balance × APR/12; payment from the annuity formula P·i / (1 − (1+i)−n). Results are estimates and exclude fees your lender may charge.