How to Convert TIBC µg/dL to µmol/L
Total iron-binding capacity (TIBC) estimates how much iron your blood could carry if all the transferrin were saturated. US labs report it in µg/dL, while most other countries use µmol/L. Because TIBC is expressed as an iron-binding capacity, it uses the same conversion factor as serum iron, 0.179.
TIBC µmol/L = TIBC µg/dL × 0.179 TIBC µg/dL = TIBC µmol/L ÷ 0.179 TIBC µg/dL to µmol/L Chart
Reference ranges vary by laboratory; compare with the range printed on your own report.
| µg/dL | µmol/L | Typical context |
|---|---|---|
| 200 µg/dL | 35.8 µmol/L | Low (seen in iron overload / chronic disease) |
| 250 µg/dL | 44.8 µmol/L | Lower limit of many ranges |
| 300 µg/dL | 53.7 µmol/L | Mid-normal |
| 350 µg/dL | 62.7 µmol/L | Normal |
| 400 µg/dL | 71.6 µmol/L | Upper-normal |
| 450 µg/dL | 80.6 µmol/L | Upper limit of many ranges |
| 500 µg/dL | 89.5 µmol/L | High (often iron deficiency) |
µmol/L to µg/dL Reverse Chart
| µmol/L | µg/dL |
|---|---|
| 45 µmol/L | 251 µg/dL |
| 50 µmol/L | 279 µg/dL |
| 60 µmol/L | 335 µg/dL |
| 70 µmol/L | 391 µg/dL |
| 80 µmol/L | 447 µg/dL |
Normal TIBC Reference Range
A typical adult TIBC range is about 250–450 µg/dL (44.8–80.6 µmol/L). Ranges differ by laboratory and assay, so always use the interval on your own report.
What High and Low TIBC Mean
TIBC is unusual because it often moves in the opposite direction to serum iron. When iron stores are low, the body produces more transferrin to capture iron, so TIBC rises in iron deficiency. When the body is iron-loaded or chronically ill, TIBC falls. Reading TIBC together with serum iron and ferritin reveals the pattern:
| Pattern | TIBC | Serum iron | Transferrin saturation |
|---|---|---|---|
| Iron deficiency | High | Low | Low (<16%) |
| Iron overload / hemochromatosis | Low | High | High (>45–50%) |
| Chronic disease / inflammation | Low | Low | Normal or low |
TIBC is also used to compute transferrin saturation (serum iron ÷ TIBC × 100) and relates to UIBC by TIBC = serum iron + UIBC. Pair it with ferritin for a complete iron-studies picture.
Worked Example
Suppose your TIBC is 480 µg/dL and you want µmol/L:
480 × 0.179 = 85.9 µmol/L 85.9 µmol/L is above the usual upper limit, a pattern often seen with iron deficiency. For the reverse direction, 50 µmol/L is about 279 µg/dL.
Frequently Asked Questions
How do you convert TIBC µg/dL to µmol/L?
Multiply µg/dL by 0.179. For example, 350 µg/dL equals about 62.7 µmol/L.
What is a normal TIBC?
About 250–450 µg/dL (44.8–80.6 µmol/L) in adults, varying by lab.
Why is my TIBC high?
High TIBC usually reflects iron deficiency, because the body makes extra transferrin to capture scarce iron. It is interpreted with serum iron and ferritin.
Is TIBC the same as transferrin?
They are closely related. TIBC is the iron-binding capacity, most of which is transferrin; some labs estimate one from the other.
References
- Merck Manual Professional Edition — Iron Deficiency Anemia (TIBC, serum iron, and iron-studies interpretation).
- Iron atomic weight 55.845 g/mol — SI conversion factor 1 µg/dL = 0.179 µmol/L (standard clinical laboratory unit conversion).
Conclusion
Converting TIBC between µg/dL and µmol/L is a simple multiply or divide by 0.179. Remember that TIBC tends to rise in iron deficiency and fall in overload, so interpret it alongside serum iron, transferrin saturation, and ferritin with your healthcare provider.