system
A chat on subreddit /r/NoStupidQuestions
human
I pay 48% taxes on an income of slightly less than 20k with VAT being 25%, electricity and cars being about 66% taxes (having almost a 200% tax added).

Not the most scientific analysis, but googling "30k us taxes" (so adding a buffer of 10k) places federal taxes at $2,500 andSocial security and medicare tax at approximately $2,300.

That's slightly less than a 16% tax rate.
gpt
US taxes don't include healthcare. Mine here in Norway included it. Any comparison with the US needs to include health costs if one is paid for mostly by taxes.. Otherwise, it isn't a fair comparison. 

And I'll note that my tax rate in Norway has never been that high for so little money. It really only happens at those incomes if you or your employer messed something up on taxes. Or possibly a second income or a vert high family income. Folks claim taxes are high here too.... Where the heck are you?