I heard her interviewed on the radio and she said as a baby it was red but it changed to brown as she got older. She liked the red-hair look so she died it when she was 13 but it wasn't crazy red like it is now.
Okay, first of all, 'haley22' really needs to get a life. First of all, the real Hayley has much better things to do than go around scoping out sites to see if people are arguing about her hair. Secondly, if you're gonna pretend to be somebody, maybe at least make sure you spell their name right, dumbass.
Now, to answer the question, when Paramore came through here on the tour where they opened for No Doubt, Hayley was asked this question in an interview on a local radio station. She said that the 'dyed so many times I can't remember' was the "official story" they were giving years ago, because they thought it added to the appeal of her always changing color... but unofficially, when she was young her hair was sort of a strawberry blonde, but as light hair colors often do, eventually started to go very dirty blonde / light brown over the years. So now, when her roots grow out it's said dirty blonde / light brown.