Thyroid Hormone Ratio Calculator

Need your thyroid hormone ratio? This calculator can calculate it for you!

Enter your lab results (Free T3 and Reverse T3) in the fields below. Select the correct unit of measurement recorded on your results sheet and click submit to see the result.




To better understand the importance of your result, read my article “Thyroid Hormone Help: How to Boost Your Thyroid Naturally“.

To make a long story short, excess Reverse T3 is a growing problem for thyroid patients. It can be caused from chronic adrenal dysfunction as well as having low ferritin/iron problems. Even low B12 and other imbalances, plus chronic stress, can cause the excess. But the Reverse T3 result by itself does not tell the whole story! You need to look at it in relation to the Free T3. This is why my Thyroid Converter is so important.

Here’s what to look for: With the Free T3/RT3 ratio, healthy ratios will be 2 or higher.

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