What this calculator does
Transferrin saturation (TSAT) works out the share of iron-carrying protein that is actually loaded with iron. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
FormulaTSAT (%) = (Serum iron / TIBC) × 100
The inputs explained
| Field | What to enter |
|---|---|
| Serum iron (µg/dL) | A number, measured in µg/dL. Starts at 100. |
| Total iron-binding capacity (TIBC) (µg/dL) | A number, measured in µg/dL. Starts at 300. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with serum iron
Every other input is held at the calculator’s starting values while serum iron varies. Select any row to load that scenario into the calculator.
How the answer changes with serum iron
| Serum iron (µg/dL) | Transferrin saturation | Typical reference range | Reading |
|---|---|---|---|
| 50 | 16.7% | 20% - 50% | Below the typical range: can suggest iron deficiency |
| 75 | 25.0% | 20% - 50% | Within the typical range |
| 100 | 33.3% | 20% - 50% | Within the typical range |
| 150 | 50.0% | 20% - 50% | Within the typical range |
| 200 | 66.7% | 20% - 50% | Above the typical range: can suggest iron overload |
| 300 | 100.0% | 20% - 50% | Above the typical range: can suggest iron overload |