How much food can you eat per day? Here a very convenient BMR calculator
BMR or Basal Metabolic Rate is the amount of daily energy (kcal, kilo calories) expended by humans and other animals at rest. At REST is very important here. It means that if you do activities then the amount indicated here is too low.
If you just sit all day, not moving, eventually watching TV and pressing on the remote control every now or then or playing video games on you Playstation or Xbox all day, night long, this would be the amount of calories you need per day. Be careful, you should not eat this amount of calories in chips or pop corns only. Fruits and vegetables are part of the deal.
The ideal weight is personal and defined by your own affinity. Some like to be light weighted and some like to have some reserve around the hips. All is acceptable. At the end, the most important is your health. So to keep it you have to stay in certain boundaries. Limits that you set yourself, it's about the exercise you're doing everyday, the amount of time you spend at work, the amount of time you spend with your family, the amount of food you eat, the amount of time you spend in front of the TV, it's only your personal decision.
The BMR calculator gives you just an indication about the number of calories that you can eat everyday in order to maintain a certain weight