Functional Endocrinology Standard
Deiodinase 1 & 2 Evaluator
Conversion Calculator
Deiodinase 1 & 2 Evaluator
Conversion Calculator
Free T3 to Free T4 Ratio Calculator (Peripheral Conversion)
Evaluate peripheral deiodinase enzyme efficiency. Approximately 80% of active T3 is produced outside the thyroid gland via selenium-dependent 5′-deiodinase in the liver and kidneys.
Standard reference range: 2.3 – 4.2 pg/mL
Standard reference range: 0.8 – 1.8 ng/dL
Deiodination Ratio Output
Molar FT3:FT4 Conversion Kinetics
Borderline Sluggish
2.00
Calculated Free T3 / Free T4 Ratio
Mild Peripheral Conversion Deficit
Your calculated ratio is slightly below the optimal functional window (2.5 to 3.3). This suggests that while storage T4 is present, 5′-deiodinase activity may be constrained by selenium deficiency, low ferritin, or chronic hepatic inflammation.