Hi,
I wanted to know the number of days (180 or 183) for not being taxed in U.S.
Thanks for your advise.

Regards
Anil.

You always pay US tax on your US source income.

If you get to 183 days in the US you're a resident and then you're taxed on your worldwide income (from US and foreign sources).

This is a gross simplication... but it gives you a general picture.

TTE's example does give you a general picture of the situation.