Ideal Body Weight Using the Post-Op Calculator on This Site

on 2/13/20 11:37 am

Quick tip: the BMI calculator is accurate by the IBW (Ideal Body Weight) numbers are way off.

To get the right number get out your iPhone and do very basic math:

For women, start with 100 lbs for your first 5'0 and add 5 lbs per inch after that.

For men, start at 106 lbs for the first 5'0 and multiply by 6 for every inch over that.

And remember, this is a just a reference tool mostly for healthcare practitioners. For the average person with a medium frame, their IBW number is lower than their normal, healthy weight.

on 2/13/20 1:18 pm, edited 2/13/20 5:19 am
RNY on 06/03/15

yea - IBW doesn't work for everyone. Me, for example. I'm 5'6", so according to this I should weigh 130. At 146, I had a body fat level of 22%, which is considered lean for a woman. My PCP said she didn't want to see me drop below 140 (which I did at one time...but I've since bounced up). So 130 for me would be way too light (for my bird-boned who's also 5'6" MIL, though, who currently weighs around 115, 130 would be fine, though (she could stand to put on about 10 lbs, IMHO....)

on 2/13/20 3:38 pm

My ideal body weight is around 120... yeah... not going to even consider that weight because I looked sickly at 145ish. I sit currently between 155-160 and I am pretty comfortable with that but I am still considered "overweight". I can't make everyone happy, but I'm the only one that matters, so I'm good!

Sparklekitty, Science-Loving Derby Hag
on 2/13/20 8:20 pm, edited 2/13/20 12:20 pm
RNY on 08/05/19

Doesn't work for me.

I'm 5'5", that sets my ideal body weight at 125lb.

Right now, I'm 160lb and 30% body fat. (111lb lean mass)

125lb would work out to be 11.2% body fat; "healthy" range for women my age is about 20 - 30%.

So nope.

Sparklekitty / Julie / Nerdy Little Secret (#42)
Roller derby - cycling - triathlon
VSG 2013, RNY conversion 2019 due to GERD. Trendweight here!

on 2/14/20 12:34 pm - GTA, Ontario, Canada
RNY on 11/15/13

I am 5'5" as well and my current weight today is 128.4 lbs and I for sure have been lower at 125 lbs and it was fine for me and my body fat was never that low (11.2% that you state at 125lbs) so don't assume it would be that if you did get down to 125-130lbs, it might but it might not.

Daisy 5'5" HW: 280 SW: 254 CW: 125 - 130

Nov 15, 2013 - RNY - Toronto Western Hospital

Nov 2, 2017 - Gallbladder removal & hernia repair

Answers to your problems are not at the bottom of a chip bag or in a box of Oreo's! You can do this!

Citizen Kim
on 2/14/20 5:31 am - Castle Rock, CO

If I were 40 years younger maybe.

At this age, super skinny would make me look like I were ready to snuff it!

I aim for maintaining a healthy weight and lifestyle - gaunt is not a good look on older people.

Proud Feminist, Atheist, LGBT friend, and Democratic Socialist

on 2/14/20 6:22 am
VSG on 02/13/19

So at 5 ft 9 I'm supposed to weigh 160? Last time I weighed 160 was in the 4th grade.



Day of Surgery-347


Laura in Texas
on 2/14/20 8:37 am
RNY on 09/17/08 with

If you truly hope to become a registered dietician working in bariatrics, you really should do more research into ideal body weight and how that applies to people who are/were morbidly obese. We need to strive for a healthy weight which may or may not be close to the BMI calculator but for most of us does not work with your IBW equation.

Laura in Texas

53 years old; 5'7" tall; HW: 339 (BMI=53); GW: 140 CW: 170 (BMI=27)

RNY: 09-17-08 Dr. Garth Davis

brachioplasty: 12-18-09 Dr. Wainwright; lbl/bl: 06-28-11 Dr. LoMonaco

"May your choices reflect your hopes and not your fears."

on 2/19/20 2:16 pm - Garland, TX

Also, keep in mind that the goal of WLS (or the practical effect, however you look at it) is to get the obese or MO down to a non-obese weight, even if technically still "overweight" (and for those of us who were super-obese before, to just "obese) .. I'll never forget the WLS surgeon (not mine, btw) many years ago who told our group of "hopefuls" to NOT expect to end up at a normal weight (and therefore certainly not "ideal" weight) b/c of the surgery itself. Otherwise we would be just fooling ourselves with unrealistic expectations, as, in his experience, that rarely happens.

Frank talk about the DS / "All I ever wanted to be was thin, like that Rolling Stones dude ... " 

 HW/461  LW/251 GW187 CW/315 (yep, a DS semi-failure - it happens  :-(    )

H.A.L.A B.
on 2/14/20 12:12 pm

IMO -That may work for some teenagers. Skinny young. Or models. Though only skinny models... not the normal ones. ]

I have a large frame, muscles. Based on the calculations for IBW I should be 117.5lbs. At 151 lbs my body fat % was 21%. My lean body weight (bones, muscles, liquids) was 119 lbs. So even If I got rid of the last 32 lbs of fat, I could not reach that number.

Hala. RNY 5/14/2008; Happy At Goal =HAG

"I can eat or do anything I want to - as long as I am willing to deal with the consequences"

"Failure is not falling down, It is not getting up once you fell... So pick yourself up, dust yourself off, and start all over again...."

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