1 hour for domestic and 2-3 for international. I have gotten to the airport with less than 30minutes to boarding time and still had lots of time:P but I was a nervous reck the whole time.
It never hurts to be early.
If you want to save more time, you can check in online and then all you have to do is check your baggage, security and your done!
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If one, settling a pillow by her head,
Should say: "That is not what I meant at all. That is not it, at all."