Car Loan Calculator
Use this car loan calculator to estimate your monthly repayment, total interest and total cost after a deposit or trade-in, and compare finance options.
What it does
The Car Loan Calculator estimates the monthly repayment on a vehicle loan, plus the total interest and total cost, after accounting for a deposit and any trade-in.
Data sources & parameters
The figures below drive this calculator. We keep them aligned with the latest official guidance, and each result recalculates automatically whenever a value changes.
| Parameter | Value | Source | Last updated |
|---|---|---|---|
| Default auto loan rate % | 6.5 | federalreserve.gov | — |
We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.
The formula
Payment = A × i ÷ (1 − (1 + i)^−n), where A = price − deposit − trade-in
How it works
The amount financed is the vehicle price less the deposit and trade-in. That amount is amortized at the monthly interest rate over the number of monthly payments.
Where it is used
- Working out repayments before buying a car
- Comparing dealer finance against a bank loan
- Seeing how a larger deposit lowers repayments
Worked example
A buyer finances a $35,000.00 car with a $5,000.00 deposit and a $3,000.00 trade-in at 8% over 60 months. The monthly repayment is …, with … of interest and a total cost of ….
What the car loan calculator does
Enter the vehicle price, your deposit, the value of any trade-in, the interest rate and the loan term. The car loan calculator shows your monthly repayment, the total interest and the total cost of the car once finance is included, so you know the numbers before signing paperwork or negotiating at a dealership.
How repayments are calculated
A car loan is amortising: each repayment covers interest and part of the principal, with early payments weighted toward interest. The amount financed is the price minus your deposit and trade-in, interest is applied monthly, and the term is the number of monthly payments. Interest is charged on the outstanding balance, so borrowing less or shortening the term reduces the total interest.
A loan with a slightly higher rate but a shorter term can cost less overall than a low-rate loan stretched over many years, because you pay interest for less time. That is why the calculator shows total interest and total cost next to the monthly figure.
Deposit and trade-in
A deposit or trade-in reduces the amount you borrow, which lowers both the monthly repayment and the total interest, since interest is charged only on what you borrow. Try different deposit amounts to see how much a larger upfront payment saves.
Choosing the term
A longer term lowers the monthly payment but raises the total interest; a shorter term does the opposite and you own the car sooner. Choose the shortest term whose repayment fits comfortably in your budget.
Match the term to how long you expect to keep the car. A very long loan can leave you still owing money on a car that has aged and lost much of its value, sometimes called being underwater on the loan.
Look at the total cost
Dealers and lenders often emphasise the monthly payment, but a low payment over a long term can mean far more interest. When comparing offers, look at total interest and total cost; a slightly higher payment over a shorter term often saves a lot.
Comparing finance options
Ask each lender for a comparison rate, which folds fees into one figure. Keep the amount and term the same when comparing. Watch for balloon or residual payments that lower the monthly cost but leave a large sum owing at the end. Running each offer through the calculator with the same inputs shows which is cheaper.
Arrange your finance before visiting a dealership. If you know what a competitive loan costs, you can negotiate the car price and the finance separately; dealers sometimes offer an attractive price and recover margin through the finance, or the reverse.
Reading your result
The repayment and interest figures are calculated from your inputs, but a lender may add establishment or ongoing fees that change the final cost, and your actual rate depends on your credit profile and the lender. Compare scenarios, such as a bigger deposit, a shorter term or a lower rate, before you commit.
This article is general information only and is not financial advice.
About This Car Loan Calculator
Use this car loan calculator to get an instant, accurate estimate. The figures follow official guidance and every rate and threshold is kept up to date for 2026. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.
Frequently asked questions
How does the car loan calculator work?
How does a bigger deposit change the repayment?
Does the calculator include fees?
What loan term should I choose?
Is my information saved anywhere?
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