I know we can only stay up to 90 days on one visit to the US, but does anybody know how many days can you be there in a year. I was thinking 90 days a year, but not sure.
AFAIK, it's 90 days in one visit. Provided you leave on or before the 90 days, you can come back for another 90 days straight afterwards.
Obviously, if you do 90 days, back for one then another 90 day and so on, Immigration are going to be looking at you very carefully to make sure you are not working etc.