How do you deal with tax if you are located in Japan?

[sayafernandes]

Hello,

My sister in law is thinking of joining Upwork and she's wondering how tax works.

I live in Europe so I don't know anything about it.

Is she going to be charged and if so, what's the rate?

If not, is she supposed to declare it?

[kc_subodh]

I don't know about Japan either but will give you USA scenario, hoping it helps a bit.

Yes, she will be liable to pay taxes. and the rate will depend on how much she earns. 
if it is less than $600 you dont have to report it but more than that you have to report it. you will also receive w2 from Upwork. 

also check this 
https://www.japan-guide.com/e/e2206.html

[sayafernandes]

Thank you! I'll be checking out the link.