Really don't know where to post this so I'm trying it in here.

I know the only really accurate BMI check is with the calipers etc but I'd be happy with a reasonable estimate.
I've had such ridiculously variable estimates from different web based calculators and scales that it almost seems pointless. Anything from 26.5% to 31%!
My home scales are the worst. Being brutal on myself I've used that as my benchmark on my profile. However I've noticed many other profiles where the weight and height is the same as mine but BMI is lower.
The accompanying statements about when your OK, not OK, obese, unhealthy. within acceptable etc etc are all different too.
Can anyone point me in the direction of an online BMI calculator which makes some sense please?

BMI calculators are pretty standard how tall are you and how many pounds do you weigh. I think what you are looking for is a calculator to give you body fat %. I finally gave up looking for a good one on line and went to the gym and had a fitness test and calipers done. I came in at 20% with the calipers. My body fat scale tells me I'm at 31% if I'm a female and 19% if I'm a male. Needless to say, I don't believe that silly body fat scale.

BMI (Body Mass Index) is not a measure of body fat.

The various measures of body fat percentage are just estimates. The only true way to measure body fat is through a biopsy. The water immersion method is cited as the most accurate estimate, with body skin-fold measurements (calipers) being next. The skin-fold measurements are very operator sensitive, so it is best to have the same person do the measurements every time.

The body measurements formulas and scales (bioimpedance) are less accurate. They are good for tracking changes in body composition, but don't rely upon the actual number as being correct.