How accurate is CarFeeCalc?
For the government portion of a vehicle purchase — sales or use tax, title, registration and plate fees — these figures are calculated from each state's own published fee schedule and statute rather than a national average. Across 15 states the engine reproduces 25 worked examples published by the agencies themselves, cites 69 primary sources, and prints the date every figure was last checked. It deliberately excludes dealer-set charges — documentation fees, add-ons and market adjustments — because those vary between dealerships in the same town, and a guessed figure would make the state comparison meaningless. The number here is the part fixed by law: identical at every dealership in your state, and therefore the benchmark you can hold a quote against.
Maintained by Arthur Patch · Figures on this page are generated from the site's own data, last verified
What is included
- Sales or use tax, at your combined state, county and city rate — looked up from your ZIP across 1,425 mapped ZIP codes in the 10 states where local rates vary, not typed in by you.
- Title fees, at the state's published amount.
- Registration and plate fees, using the state's actual model — flat, weight-based, value-based or MSRP-based — including EV and hybrid surcharges where they apply.
- Your state's trade-in and rebate rules, applied automatically. You do not need to know them.
- Renewal costs, projected year by year, because the first year is rarely what you keep paying.
What is excluded, and why
Everything below is excluded on purpose. Each is set by the seller rather than the state, so including a guess would corrupt the figure that is genuinely knowable.
- Dealer documentation fees. Capped by statute in some states, unlimited in others — the caps are here.
- Dealer add-ons and market adjustments. Paint protection, nitrogen tyres, tracking devices, above-MSRP markups. Unpredictable by nature — what they are and how to remove them.
- Lien recording, warranties, gap insurance and financing charges.
- Late penalties, proration and temporary tags, and the credits available when transferring a plate you already hold.
- Exemptions for disability plates, military service, new residents, gifts and inherited vehicles, which follow separate rules in most states.
How a figure gets verified
Every fee is taken from the agency that charges it — a published fee schedule, an administrative rule, or the statute — and never from another calculator. Where an agency publishes a worked example, the engine is run against it and must reproduce the published number exactly; 9 of the 15 states here carry at least one such check, 25 in total, and they are printed on the state pages so you can see what was matched. The calculation logic itself is covered by 223 automated tests that run on every deploy, and each state's distinctive rules are pinned by tests written to fail if the rule is removed.
Where two credible sources disagree, or a fee is real but its exact amount cannot be confirmed, it is marked as an estimate rather than presented as fact. The full rules are in the editorial policy, and every correction is dated in the changelog.
The limits, stated plainly
Fee schedules change and this site lags them. Each state page prints the date its figures were last checked — currently at the most recent and at the oldest — and a figure verified in August will not reflect a September change until it is re-checked. Local rates can also carry special district additions above the base city rate; where a state is prone to that, its page says so.
None of this makes an estimate into a quote. The disclaimer sets out the full position. If you find a figure that is wrong, reporting it with the official source gets it corrected first — that is how several of the figures here reached their current form.
How to use it against a dealer quote
Run your price and ZIP through your state's calculator — or paste the quote into the quote checker — then ask the dealer for an itemised out-the-door figure. The tax, title and registration lines should match closely, because those are statutory. Anything above them is the dealership's own — the doc fee, the add-ons, the adjustment — and that is the negotiable part. On the same $30,000 car, the government portion alone ranges from $555 in South Carolina to $3,377 in California, so knowing your state's real number is what makes the comparison possible at all.
Frequently asked questions
- How accurate is CarFeeCalc?
- For the government portion of a vehicle purchase — sales or use tax, title, registration and plate fees — the figures are calculated from each state's own published fee schedule and statute, not from a national average. Across 15 states the engine reproduces 25 worked examples published by the agencies themselves, and every figure carries the date it was last checked against its source. It does not predict dealer-set charges: documentation fees, add-ons and market adjustments are excluded by design, because they vary between dealerships in the same town and including a guess would make the state figures meaningless.
- Does CarFeeCalc handle trade-in and rebate rules correctly?
- Yes, automatically — you do not need to know your state's rule. Each state's treatment is encoded from its statute and applied when you enter a figure: California gives no trade-in credit at all, Michigan caps it at $12,000, and the rest deduct the full allowance. Manufacturer rebates reduce the taxable amount in Arizona, Missouri, Texas and Georgia and are taxed in the others. Where a rule limits your deduction, the calculator says so in the result rather than silently applying it.
- Why does the calculator exclude dealer doc fees?
- Because they are set by the dealer, not the state. The same car at two dealerships a mile apart can carry doc fees hundreds of dollars apart, so a figure that included a guessed doc fee would not be comparable between states or between dealers. Excluding it makes the number here the government portion: fixed by law, identical at every dealership in your state, and therefore the benchmark you can hold a dealer quote against.
- Will my dealer bill match this estimate?
- The tax, title and registration lines should be close — those are set by statute. Your total will be higher, because a dealer adds their own documentation fee and any add-ons or market adjustment. Use the figure here as the government baseline: the gap between it and the dealer’s out-the-door total is the dealer’s own charges, which is exactly the part worth questioning.
- How current are the figures?
- Every state page prints the date its figures were last checked against the source; the most recent across the site is 20 August 2026 and the oldest is 18 August 2026. Fee schedules change without notifying websites, so a figure verified in one month will not reflect a change made the next until it is re-checked. Where a fee is real but its exact amount could not be confirmed against a primary source, it is marked as an estimate rather than presented as fact.
- Where do the local tax rates come from?
- From each state's own rate tables, mapped to 1,425 ZIP codes across 135 jurisdictions in the 10 states where local rates vary. Enter a ZIP and the combined state, county and city rate for that jurisdiction is applied — rather than asking you to look your own rate up, which is where most calculators put the burden and most errors originate.
Related: editorial policy, dealer doc fees, and every state compared.