Good morning luvs. first things first...... I want to thank everyone who gave me advise. Update!!!! Feeling a difference already with my new addition of T3. Still not consuming the whole 5 mcg yet, working my system up to it comfortably. Listening to MY body. So this is the question and please do not answer unless you know. I have hear everything from double to 10xs!!! How much stronger is T3 than T4???? I am guessing 4Xs possibly? I seen a chart once that said under synthetics which is me, Synthroid brand and Cytomel generic 25 MCG of cytomel was equal to 100 of Synthroid, but no comparison for the 5 of cytomel i was prescribed. And then you have to factor in the % of T3 you get that is coming from the synthroid correct? Our systems transfer 40-50% is it of T4 roughly into T3...... but that's if you convert and that's if you absorb properly also. Then there are people who convert but not properly or not enough lol! Wow is this thyroid stuff a mess! Like I said please only converse with me if you are able to answer these questions. Have a wonderful day.