I used the information in Mountain Rose Herbs and made my own dilution chart in Excel. It is below; feel free to use it if you're into Excel formulas like I am. If you prefer something more simple that you don't have to update, I found the dilution chart on this blog very easy to use: Mommypotamus
I have not found a definitive source or guideline as far as dilution rates for children. Try Googling "essential oil dilution chart" and you'll see what I mean. Some sources seem overly conservative, recommending not more than a 3% dilution for children 6 years and under, which in a 10-ml roller bottle means 6 drops of oil or less. Other sources practically advocate taking a bath in undiluted essential oil (yes, that's an exaggeration, but you get my point).
My personal opinion based on observation is that the inconsistency is due to the quality of the products themselves. Obviously, if one is using a lesser-quality product full of synthetics or manipulated oils, this would not be a good idea to apply in any quantity on a child or an infirm person. That is not a concern when you're talking about pure, authentic Young Living oils. Please use your best judgement, watch for irritation, and stop immediately if your child appears to have a reaction. I do know people who have applied Young Living oils to their infants with no ill-effects, however I am a more cautious person and I personally wouldn't apply any essential oil neat (or undiluted) to a child less than 3 years old.
Here is what I use when calculating out dilution.
