Hepcidin Unit Converter
Hepcidin Unit Converter
Convert hepcidin-25 between ng/mL, µg/L, nmol/L and pmol/L, with a note on why reference ranges are not transferable between assays.
Hepcidin converter
Mass ⇄ molarHepcidin-25 12 ng/mL
Formula and conversion factor
pmol/L = ng/mL × 358.5
- 0.3585
- derived from the hepcidin-25 molecular weight, 2789.4 Da
- ng/mL
- numerically identical to µg/L
- hepcidin-25
- the bioactive 25-amino-acid form; shorter isoforms are not measured by most assays
Worked example
Hepcidin-25 12 ng/mL
12 × 0.3585 = 4.302 nmol/L
= 4302 pmol/L = 12 µg/L
Typical adult values
| Group | ng/mL | nmol/L |
|---|---|---|
| Men | 1 – 55 | 0.4 – 19.7 |
| Women, premenopausal | 1 – 25 | 0.4 – 9.0 |
| Iron deficiency | Suppressed, often undetectable | — |
| Inflammation | Markedly raised | — |
What hepcidin measures
Hepcidin is the master regulator of iron entry into plasma. Made by the liver, it binds ferroportin — the only known cellular iron exporter — and triggers its degradation, shutting off absorption from the duodenum and release from macrophage stores at the same time. Iron loading and inflammation both increase it; iron deficiency, hypoxia and active erythropoiesis suppress it.
That mechanism explains most of the iron disorders seen clinically. Anaemia of inflammation is a hepcidin-driven state: interleukin-6 raises hepcidin, iron is locked into macrophages, and the marrow is starved despite adequate stores. Hereditary haemochromatosis is the mirror image, with inappropriately low hepcidin allowing unrestrained absorption. Iron-refractory iron deficiency anaemia results from TMPRSS6 mutations that leave hepcidin inappropriately high.
Its promise as a routine test is that it would predict who responds to oral iron: a high hepcidin means oral iron will not be absorbed, and intravenous replacement is needed. That promise remains largely unrealised in practice because assay standardisation is incomplete — mass spectrometry and immunoassay methods give different absolute values, and there is no agreed reference interval. It is a valuable research measurement and a specialist test rather than a routine one.
Frequently asked questions
How do I convert hepcidin to nmol/L?
Multiply the ng/mL value by 0.3585. The factor comes from the molecular weight of hepcidin-25, 2789.4 Da.
Why is hepcidin not a routine test?
Assay standardisation is incomplete. Mass spectrometry and immunoassay methods give different absolute values and there is no agreed reference interval, so results cannot be compared between laboratories.
What does a high hepcidin mean?
Iron is being held in stores and absorption is blocked — the pattern of inflammation, infection or iron overload. Clinically it predicts that oral iron will not be absorbed.
Is hepcidin the same as hepcidin-25?
Hepcidin-25 is the bioactive form and what assays target. Shorter isoforms, hepcidin-20 and hepcidin-22, circulate but have little iron-regulatory activity.
Related calculators
References
- Ganz T. Systemic iron homeostasis. Physiol Rev. 2013;93(4):1721–41.
- Girelli D, Nemeth E, Swinkels DW. Hepcidin in the diagnosis of iron disorders. Blood. 2016;127(23):2809–13.
- UniProt P81172 — hepcidin, mature 25-residue peptide.