The Body Fat Calculation uses base 10 logarithm, where as Math.Log gives the Natural Logarithm. They are not the same thing.

To convert to base 10 log, you need to divide by the natural log of 10.

To convert to base 10 log, you need to divide by the natural log of 10.

```
LbJP.Text = 495 / (1.0324 - 0.19077 * (Math.Log((Val(TxtWaistBL.Text) * 2.54)/Math.Log(10) - (Val(TxtNeck.Text) * 2.54))) + 0.15456 * (Math.Log((Val(TxtHeight.Text)/Math.Log(10) * 2.54)))) - 450
```