doctors?

You can go to a doctor for a bodyfat analysis. If you go to a gym, there might be some personal trainers that also can do this as well. Often times, they will give a free consult or a discounted package rate. And you can request a bodyfat assessment. Depending on the equipment they are using, there is some margin of error. But at least it'll give you a baseline of which to start with?

Personally, I think bodyfat analysis is helpful for those just getting into fitness that need to lose some weight for health reasons. I am conflicted on whether they are helpful to a typical non-competing athlete because of the aforementioned margin of error. I think body measurements are a better way of assessing composition. I know that others may disagree with this, and so it could be ultimately a matter of preference.

Whatever you choose, bodyfat or measurements, try to keep track of the clothes you wear, and time of day when you get evaluated. That way, the next time you get evaluated, you can replicate the same conditions - minimizing variables that could affect the results.

Also take pictures. You can always delete them if the fitness program goes awry, but there's nothing more self-motivating than to see visual changes over time.