Yeah those calculators are more generalization, but everyone is different.
I'm 5'7" and right now about 142lb. Been 165 and looked a bit bigger. Been 135 at the end of last year, and looked EXACTLY the same as 150. If you looked at the top half of me, you'd think I was in shape. Then take a look at the bottom half, and you'd think I was nearing 170. Being pear shaped really does suck because I've seen absolutely no different on the bottom half of me which makes me think I'm not loosing any weight/inches at all and it's been over two months now.
I had first set my goal to 120. Then I bumped it down to 115. Bumped it back to 120, and finally 125. I just want to be in the 120s, because I haven't been there in my adult life (last time I was in the 120s was...oh geez, definitely elementary school). I definitely do not have a small frame, but 140 does not look right on me. I am not sure how much a 20lb difference will make as a 10lb difference doesn't do anything, but hopefully it's enough to be where I want to be. I'm hoping the last 10lb will be all thigh/butt/lower tummy (my problem areas). A girl can dream.