Enter the levels of triiodothyronine and thyroxine into the calculator to determine the T3 T4 ratio. This calculator can also evaluate any of the variables given the others are known.

## T3 T4 Ratio Formula

The following formula is used to calculate the T3 T4 ratio.

R = T3 / T4

Variables:

- R is the T3 T4 ratio
- T3 is the level of triiodothyronine in the blood (ng/dL)
- T4 is the level of thyroxine in the blood (μg/dL)

To calculate the T3 T4 ratio, divide the level of triiodothyronine (T3) by the level of thyroxine (T4). The result is the T3 T4 ratio, which can be used to evaluate thyroid function and diagnose thyroid disorders. A high ratio can indicate hyperthyroidism, while a low ratio can indicate hypothyroidism. This ratio can also help in assessing the severity of thyroid dysfunction and monitoring the effectiveness of treatment.

## What is a T3 T4 Ratio?

A T3 T4 ratio is a medical test that measures the levels of two hormones produced by the thyroid gland: triiodothyronine (T3) and thyroxine (T4). This ratio is used to evaluate thyroid function and diagnose thyroid disorders. A high or low T3 T4 ratio can indicate hyperthyroidism or hypothyroidism, respectively. It can also help in assessing the severity of thyroid dysfunction and monitoring the effectiveness of treatment.

## How to Calculate T3 T4 Ratio?

The following steps outline how to calculate the T3 T4 Ratio.

- First, determine the level of triiodothyronine in the blood (T3) in ng/dL.
- Next, determine the level of thyroxine in the blood (T4) in μg/dL.
- Next, gather the formula from above = R = T3 / T4.
- Finally, calculate the T3 T4 Ratio.
- After inserting the values of T3 and T4 into the formula and calculating the result, check your answer with the calculator above.

**Example Problem : **

Use the following variables as an example problem to test your knowledge.

Level of triiodothyronine in the blood (T3) = 2.5 ng/dL

Level of thyroxine in the blood (T4) = 1.8 μg/dL