As Jim said, your T lvls are pretty good. Your total is right at where my Dr tries to get patients at (800) and your free is right in the middle. Honestly if I were you I wouldn't want to go the TrT route yet. Did you get a full panel? If you're experiencing any symtoms of low T, it may be something else out of line?
but... as I think about this more, you might be a guy that has had high test all of his life and you may very well be feeling the affects of decreasing test.... I've read that most people can start to feel low T symptoms below 600. I would personally look at symptoms, and if you are feeling low, maybe do a trial TRT to see if your symptoms improve.
You didn't say why you were considering TRT. Is there a problem you are trying to fix?
Jim brings up a good point, there could be other issues, like thyroid. When I took care of my thyroid, I probably came up to 75%... So yea, you should run a full panel.
Most doctors don't know how to fix thyroid issues, and most look at TSH, which is a BS indicator. You should educate yourself as much as possible about thyroid issues if you think that is a possibility, so you can steer your doctor in the right direction.
You've left out the important info. What's your symptoms? Everything is relative.
Your FT4 and TSH by numbers look good on lab values of a populace given, if other Thyroid hormones are displaced improperly or not transported from an underlying nutritional deficiency or congenital or hormonal imbalance of supportive hormone interactions. Numbers are meaningless. That's only small percentage of the total equation, when we try to correct by numbers of a populace we don't know what we once was before tragedy(Sense of wellbeing) took place.
Think really hard of the last Month(s),Year(s) before all this started (if anything, you haven't given description of problem). Be your own detective, retrace steps that you done,are doing before you fell off the face of the earth, or floating in space. If you've falling or floating?
This is still at a pretty high level, but gives some more detail.
TSH is the request from the pituitary gland to the thyroid to make more thyroid hormone, so if you are in range there, then it means your body thinks you are good, if it is high, it could mean that your thyroid isn't producing enough hormone.
T4 is what is converted into the active hormone, T3, as well as other hormones such as RT3.
If T4 is in range, your thyroid is producing enough hormone, if it is below range it is not.
You can have both TSH and T4 in range and still have hypo symptoms. The next one to check is free T3. This is the active hormone, but again, it can be in range and you can still have hypo symptoms.
The best indicator is the free T3 / RT3 ratio. Essentially RT3 binds to T3 to cancel it out. If your RT3 is high, or the ratio is not right, all your other numbers can be fine, and you will have hypo symptoms.
There are also things like making sure your adrenal system is in check. If your cortisol levels aren't right, all of your hormones levels can be fine, but your body will not respond correctly.
The body is a complex system, sometimes we try to over simplify things too much, which works most of the time, but there are outlier cases.