How long are security lines at Atl?

20-30 minutes

Read everything about it here. In respect to this, how long does Atlanta security take?

TSA recommends getting to the terminal at least one hour early for domestic travel and at least two hours for international travel. Here's a guide to help you navigate security at the Atlanta airport.

Likewise, how long does it take to get through customs in Atlanta airport? about 30-45 minutes

Keeping this in consideration, how early do I need to arrive at Atlanta airport?

Airport and TSA officials in Atlanta recommend getting to the airport terminal two hours before domestic flights and three hours before international flights.

What time should I arrive at Hartsfield Jackson?

While the Transportation Safety Administration (TSA) recommends travelers arrive two hours before a domestic flight and three hours prior to an international trip, “those are just general times,” says Richard Duncan, the Assistant General Manager of Public Safety and Security at Atlanta's Hartsfield-Jackson