Calorie Allotment

Height? Weight? Age? Gender? These are all factors.

Are you all identical?

Not identical. Two of us want to lose 20, one wants to lose 40. We're all the same age.

The factors are height, current weight, age, sex, activity level, and how fast you want to lose. If all of those factors are the same and you're getting different results, you've input something wrong. But I doubt that's the case.

Will the one at 1650 drop down to 1450 once she loses weight? Or does it not work like that?

It works exactly like that! ~Every so often MFP recalculates based on your weight, so its important to log weight loss as well as food and exercise

So is it the greater the weight, the more calories you get?

Because we're different in height and current weight, but around the same with age, sex, activity level, and how fast you want to lose.

Will the one at 1650 drop down to 1450 once she loses weight? Or does it not work like that?

Yes, I think the daily calorie goal will decrease with weight loss. I am not 100% sure, just because my calories are 1200 no matter what I enter as my weekly weight loss goal or activity level. I think that's the minimum. My goal is to lose 12 lbs, and I'm only 5'1". Either way, you do what is most comfortable and doable for you. Some days 1650 will be more than enough, sometimes you'll be starving! lol Good luck!!

I believe it changes your calorie amount with 10 pounds loss. It gives you a message saying you're lost 10 pounds or whatever, and asks if you want to change your goals.