How much tax am I going to pay on foreign income?

I am earning a monthly income from being a virtual assistant for a company based in the US and earning dollars. It is paid via PayPal and drawn through my bank. This is a second income, not my main form of income. It is part-time work. How much tax am I going to pay?

Please make use of our SARS income tax calculator to work out how much tax you need to pay.