About Contact
Tools
1 Rep Max Calculator — Estimate Your 1RM From Any Set401(k) CalculatorAge Calculator — Your Exact Age in Years, Months & DaysAmortization CalculatorAsphalt CalculatorAsphalt Driveway Cost CalculatorAuto Loan CalculatorBarcode GeneratorBase64 EncoderBd Ft CalculatorBench Press Max Calculator — Estimate Your Bench 1RMBMR Calculator — Estimate Your Basal Metabolic RateBoard Foot CalculatorBrick CalculatorCalorie Deficit Calculator — Daily Target and TimelineCD Calculator (Certificate of Deposit)Cement CalculatorCircle Area Calculator — Area, Radius, Diameter, CircumferenceColor Palette GeneratorCompound Interest CalculatorConcrete Bag CalculatorConcrete Block CalculatorConcrete CalculatorConcrete Calculator with CostConcrete Footing CalculatorConcrete Mix CalculatorConcrete Pad CalculatorConcrete Price CalculatorConcrete Slab CalculatorConcrete Slab Cost CalculatorConcrete Volume CalculatorConcrete Weight CalculatorConcrete Yard CalculatorConduit Fill CalculatorCrushed Stone CalculatorDirt CalculatorDrywall CalculatorDue Date Calculator — Estimate Your Baby's Due DateFantasy Name GeneratorFavicon GeneratorFence CalculatorFill Dirt CalculatorFinal Exam Calculator — What Grade Do I Need on the Final?Fraction Calculator — Add, Subtract, Multiply, DivideFree Citation Generator (APA, MLA, Chicago, Harvard)GPA Calculator — Unweighted and Weighted, with Cumulative GPAGravel CalculatorHEIC to JPG ConverterHELOC CalculatorInsulation CalculatorLandscape Rock CalculatorMacro Calculator — Daily Protein, Carbs, and FatMean Calculator — Average of a List of NumbersMedian Calculator — Middle Value of a List of NumbersMeme GeneratorMetal Roof CalculatorMinute to Decimal ConverterMorse Code ConverterMortgage Payoff CalculatorMulch CalculatorOvulation Calculator — Find Your Fertile WindowPaver Base CalculatorPaver CalculatorPaver Sand CalculatorPea Gravel CalculatorPeptide CalculatorPercentage Calculator — Solve Any Percent QuestionPNG to PDF ConverterPuppy Weight CalculatorPythagorean Theorem Calculator — Solve Any Right TriangleQuadratic Formula Calculator — Roots, Vertex, Factored FormQuikrete Concrete CalculatorRaised Bed Soil CalculatorRandom Name GeneratorRiver Rock CalculatorRock CalculatorRoof Cost CalculatorRoof Pitch CalculatorRoof Shingle CalculatorRoof Slope CalculatorRoof Truss CalculatorRubik's Cube Solver — Solve Any Scrambled 3×3 CubeSakrete Concrete CalculatorSales Tax CalculatorSand CalculatorScrap Silver CalculatorSignature GeneratorSleep Calculator — Best Bedtimes & Wake Times by Sleep CycleSlope Calculator — Slope, Equation, Angle, GradeSnow Day CalculatorSod CalculatorSoil CalculatorSonotube Concrete CalculatorSquare Footage Calculator — Room and Floor AreaSquat Max Calculator — Estimate Your Squat 1RMStandard Deviation Calculator — Sample and PopulationStone CalculatorTDEE Calculator — Total Daily Energy ExpenditureTier List MakerTile CalculatorTime Calculator for WorkTop Soil CalculatorTopsoil CalculatorTriangle Calculator — Solve Any Triangle From 3 InputsUPC GeneratorUsername GeneratorVolume Calculator — 8 Shapes With Unit ConversionWebP to JPG ConverterWebP to PNG ConverterWordle Solver — Best Next Guess for Today's Puzzle
← All tools

Auto Loan Calculator

Monthly payment, total interest, and full amortization — with state sales tax built in.

Tax treatment
Term
Monthly payment—
Financed principal—
Cash at signing—
Total interest—
Total of payments—

What is auto loan calculator?

An auto loan is a fixed-rate amortizing loan — the math is the same as a mortgage, just with a smaller principal and a shorter term. What makes auto-loan calculations specific is the up-front costs around the purchase: sales tax, registration, doc fees, and the credit you get for trading in your existing vehicle. Get these wrong and the financed amount can be off by thousands.

The calculator handles them as follows. Tax base is price − trade-in, multiplied by your state’s sales-tax rate. Financed principal is price − down − trade-in + fees + (taxFinanced ? tax : 0). Cash at signing is down + (taxFinanced ? 0 : tax). Monthly payment comes from the same standard amortization formula every fixed-rate loan uses: M = P × r / (1 − (1 + r)^−n).

Trade-in treatment is the most common source of confusion. In most states, the credit reduces both the financed principal and the tax base, so a $5,000 trade-in on a $30,000 car in California (7.25%) saves you $5,362.50 — five grand off the loan plus $362.50 in tax. The exception is the handful of states that tax the full vehicle price regardless of trade-in: there the tax savings disappear and only the principal reduction applies. The FAQ above lists those states. When in doubt, verify with your state’s DMV before relying on the calculator for the exact tax number.

When to use a auto loan calculator

  • Comparing two dealer offers — Two dealerships quote different APRs and down payment combos on the same vehicle. Run each through the calculator to see total cost over the loan, not just the monthly figure.
  • Budgeting cash at signing — A buyer wants to know how much money to bring to closing. The calculator splits the total into what's financed and what's paid in cash up front.
  • Tax-rolled-in vs paid-at-signing — Some buyers prefer to pay sales tax in cash to keep the loan smaller; others roll it in to preserve cash. Toggle between modes and see the monthly payment change.

How to use the Auto Loan Calculator

  1. Enter vehicle price, down payment, and trade-in — Vehicle price is the negotiated price before any taxes or fees. Down payment is cash you'll bring to signing. Trade-in is the value the dealer credits for your existing car.
  2. Pick your state for the sales-tax rate — The dropdown loads each state's base sales-tax rate. If your city/county adds local tax, pick 'Custom rate' and enter your combined rate. Tax is computed on (price − trade-in) — the standard treatment in most US states.
  3. Choose tax treatment — Roll the tax into the loan to keep cash at signing low, or pay it at signing to keep the monthly payment lower. The calculator shows both effects.
  4. Set APR and term, review the schedule — APR is the rate the lender quoted. Term defaults to years; switch to months for a 36/60/72-month finer cut. Expand the schedule for month-by-month detail and download or print.

Worked examples

Standard new-car deal

Input:  $35,000, $5,000 down, $0 trade-in, CA (7.25%), tax financed, $500 fees, 6% APR, 60 months
Output: Monthly $660, financed $32,538, cash at signing $5,000

Tax paid at signing

Input:  Same as above, but tax paid at signing
Output: Monthly $611, financed $30,500, cash at signing $7,538

Trade-in lowers tax base

Input:  $35,000 + $8,000 trade-in, CA. Tax is on $27,000 not $35,000.
Output: Tax $1,957.50 (not $2,537.50)

Most states tax the net (price minus trade-in), giving a real tax savings on a trade-in.

Frequently asked questions

Is sales tax really included?
Yes — the calculator looks up your state's base sales-tax rate from a built-in table and applies it to (price − trade-in). Most states give a tax credit for trade-ins, which the formula reflects. If your jurisdiction adds local tax on top of state, use 'Custom rate' to enter the combined figure.
Does my state really tax (price − trade-in) and not just (price)?
Most do, but not all. The states that tax the full price regardless of trade-in include California, the District of Columbia, Hawaii, Kentucky, Maryland, Michigan, Montana, Virginia. If you're in one of those, the calculator under-counts the tax — the cleanest workaround is to enter your trade-in as $0 and reduce the down payment manually by your trade-in value.
Should I roll tax into the loan or pay it at signing?
Mathematically, financing the tax costs you interest on those dollars over the term — for a $2,500 tax at 6% APR over 5 years, that's about $400 in extra interest. If you can comfortably bring the cash, paying at signing saves real money. If you can't, financing it isn't a disaster — just know the cost.
What APR should I expect?
Rates vary by credit score, term, and whether the loan is new vs used. As of 2026, prime borrowers (740+) on new cars typically see 5–7%; non-prime can see 10–15%; subprime 18%+. Dealer financing is often higher than direct lender financing — get a pre-approval from a bank or credit union before walking into the dealership for a real comparison.
How long should the term be?
Longer terms mean lower monthly payments but more total interest. 60 months (5 years) is a common compromise. 72 and 84 months are increasingly available but you risk being upside-down (owing more than the car is worth) for years. Shorter is generally better if the monthly fits your budget.
What goes in the 'fees' field?
Title, registration, doc fees, and any other one-time charges from the dealer that get rolled into the financed amount. Don't include the down payment or the sales tax — those have their own fields. If you want to pay any of these fees at signing instead of financing them, enter $0 here and add the amount to the down payment.
Why doesn't the math match what the dealer quoted?
Common reasons: extended warranties, gap insurance, or other add-ons rolled into the financed amount (not modeled here); a different APR than was quoted; or a state-specific tax rule the calculator doesn't model exactly. The fee field can absorb most one-time add-ons if you want to test scenarios.
Does this work for leases?
No — leases use a money-factor structure, residual value, and different tax treatment, and the math is genuinely different. This calculator is for purchase loans only.

Amortization Calculator

Generate a full month-by-month payment schedule for any fixed-rate loan.

Sales Tax Calculator

Add tax to a price or back out tax from a total — by state or custom rate.

Mortgage Payoff Calculator

See how much sooner you'll be done — and how much interest you'll save — with extra payments. Or get a per-diem payoff-quote estimate for a target date.