How accurate are bio-electrical impedance scales to measure body fat percentage? I started out at 236 pounds and am down to 215, with a goal of 195ish but I'd like to get some body fat percentage data so I can plan the best possible workout...so how accurate are they? Is accurate price dependent; because I notice prices on these things can range from $30 to $300...

Bear in mind, they do not need to be 100% accurate, but consistent. Meaning...if my body fat was 18% and it reports 22%, that's fine as long as it will report 18% once I get it down to 14%...point here being the ability to confirm progress...

Everything I've read says they're accurate to +/- 15% or so.

I bought one from Amazon - this one: Omron HBF-306C Fat Loss Monitor

It seems reasonably accurate and I've been happy with it so far.

I'm hoping you meant +/- 1.5%, not 15%, Kara.

I use the impedance monitor at my local pharmacy. I'm happy so long as the overall trend is down. I agree that it doesn't need to be 100% accurate.

Well, more accurately I guess i should have said that the variance *can* be up to +/- 15%.

What I've read says that the ones that are available for home use can be influenced by a lot of variables - including things like how much water you've had to drink prior to taking the measurement, whether you've had alcohol in the 24 hours prior to measuring, even whether you've had caffeine to drink. Also women who use them during their periods get pretty skewed results.

The lower priced ones are more susceptible to a greater variance. Supposedly the higher priced ones that are found in medical offices and so forth have closer to a 96%-98% accuracy rating.

All of that said, I did my research and decided to buy a low end one anyway - because as long as I'm careful about when and how I test, I can at least get a good ballpark of where my bodyfat percentage is.

I have the same bodyfat monitor as Kara, and I've been very happy with it. You just need to realize that there are variables, so watch for a trend of change.

I bought a cheap one. I would call it presise, but I'm not sure on the accuracy. What I mean is, it gives consistent readings, and seems to get lower at a reasonable pace as I lose weight, but I have no idea if the reading is anywhere close to what my bodyfat % really is. For the record, it says I am 40.7% fat, at 312lbs. A quick calculation says that my body has 127lbs of fat? I guess that sounds about right... If I were to lose another 80lbs of fat in an ideal world, then my body would have 47lbs of fat at 232lbs total weight, which equals 20.3% fat, so that seems about right to me.

I'll look up the scale I have later and post it here for whoever is interested.