How does the tax system work?

My wife and I are planning to permanently live in Japan, she has fallen in love with the country ever since she was a teenager and id like to go with her to live out that dream of being citizens. however i was wondering about the taxes. Is there a way of legally getting better tax rules. We have a substantial amount of money in the stock market. We want to keep investing for our financial independence. However I'd like to know if you pay taxes over this money you already have and the yield you get for example from dividends or portfolio growth. In other countries you pay money over the yield you get plus a percentage of the money you have. For example in our country we pay 32% over all the money we have if it surpasses the 57000 euro treshhold.

Additional info about living in Japan is also very welcome,
Thank you for reading and potentially answering. :)

Japan has some of the strictest inheritance and gift tax laws in the world. So, if you are wealthy, have kids and don't want to donate half of your wealth to the country, you better move somewhere else.

Is anyone if you a Japanese citizen?
If not, what is going to be your residence status in Japan?

You pay taxes on worldwide income (including dividends et al).
As mentioned above, inheritance and gift rules are also very strict.
You don't suddenly come to Japan and become a citizen. You have a lot more research to do.

for dividends, tax is 20%.
for portfolio growth, no tax, because it is hypothetical.

Here in Japan, they even tax gains on the sale of financial assets like stocks and investment trusts, generally more than 20%. When I heard that such gains are not taxed in some countries, it made me so jealous!

Anyway, how are you and your wife planning to obtain your resident status? There is no visa category for "we fell in love and want to live here." In addition, unlike some Asian countries, just being rich does not satisfy visa eligibility. Will either of you get a job offer in Japan?

I would probably speak to someone who's an expert in the tax field within Japan that can give you a very accurate answer. From what I know and others have said, the taxes are very high in Japan and you'd want to be careful not to be giving up the money you've made so far.

From an honest perspective from someone who's done a bunch of research on taxes and what's coming for the future, hold off on coming to Japan for now if you don't want to give up a bunch of your money. The whole tax system around the world is changing as we speak, so better to wait until it's actually done so that way you can keep more of what you've earned.

I do highly encourage you to DYOR so that way you can know for sure what's to come in the future.

if you think it is high, it is high. but, clever people use the system cleverly.
consult to an accountant, not ask your friends.