I’m not familiar with this formula and to be honest it looks like a bunch of kaka but I got it to work making the following adjustments:

1. (BW * 1.08) + 94.42 = A

2. (Waist around navel in inches * 4.150) = B

3. A – B = C

4. BW – C = D

5. (D / BW) = BF

6. BF * 100 = BF% *This ‘*100’ is pretty standard for these calculations to actually get the % so I took the liberty of adding it in*

This gave me a final value of 2.5% (or 0.025 if you don’t multiply by 100) which would be in the right ball park for %s. I can tell you for certain though that I’m not that low. The last time I was tested I was 6.7% with hydrostatic weighing. If Fred’s estimation is trying to simulate a caliper test it would be closer as I’ve been tested at around 2.7% using the calipers but I think they are pretty much worthless anyhow. Any time I hear an NFL lineman brag about 4-5% BF, the alarm in my head immediately goes off that 1) calipers were used to test this guy; and 2) the person administering the test didn’t know how to take accurate measurements.

As for the equation, I really don’t like the “+94.42” because using constants for this type of thing rarely ever works out well for a wide range of individuals.