Japan: consumption tax is inside, the vehicle taxes are not
Japan splits its car taxes in two, and only one half is already paid for by the time you sign. Consumption tax is inside the price, but the weight tax and registration are added on top, so the calculator keeps a rate field here and opens it at 5% of the price as a working figure. The weight tax depends on the car's mass rather than its price, so the percentage is only a stand-in, and you should replace it with the yen figures from the dealer's estimate sheet once you have them.
The purchase-side charge has been shrinking. The old acquisition tax was scrapped in October 2019 and replaced by an environmental performance levy of up to 3% of the price, graded by fuel economy, and that levy was itself abolished in the 2026 tax reform. If you are working from an older estimate sheet or an online guide, check whether it still includes it.
There is no trade-in credit. Trading a car in reduces the amount financed by its equity and leaves the weight and registration charges untouched.
Two costs that dominate Japanese car ownership are deliberately outside this calculation, because they are not purchase costs: the annual automobile tax, charged every year on engine displacement, and the compulsory inspection, due periodically for the life of the car. Neither belongs in a loan, and adding either to the fees field would overstate what you owe the lender.