Normal ferritin levels and how to read the number

Most labs report normal ferritin levels as roughly 24–336 ng/mL for adult men and 11–307 ng/mL for adult women. Those are ranges, not verdicts. Ferritin measures stored iron, so one value only means something next to the rest of the panel.

The normal ferritin levels chart, band by band

Every lab sets its own reference interval from its own analyzer and its own sample population, which is why the range printed on your report is the one that applies to your result. The bands below are the intervals large reference labs commonly publish for healthy adults. They orient you; they don't settle anything.

Band	Men (ng/mL)	Women (ng/mL)	What the band generally reflects
Depleted stores	under 15	under 15	Storage iron effectively gone
Contested low zone	15–24	15–24	Below the interval for men, still inside it for women
Reported reference interval	24–336	11–307	Inside the range the lab prints as normal
Above the interval	over 336	over 307	Most often inflammation, liver, or alcohol
Markedly elevated	over 1,000	over 1,000	Investigated regardless of how a person feels

The bands overlap, and that overlap is the whole problem. A result of 20 ng/mL sits below the interval for a man and inside it for a woman, even though the quantity of stored iron is identical. Sex-split intervals exist because menstruating women as a population carry lower stores — the range describes what's common in that group, not what's optimal for anyone in it.

Children and adolescents have their own intervals, generally lower than adult ones. Pregnancy shifts things again: plasma volume expands and fetal demand rises, so ferritin normally falls across the trimesters, and later-pregnancy results are read against pregnancy-specific expectations rather than the standard adult range.

ng/mL and mcg/L are the same number

Ferritin is reported in ng/mL in the US and in µg/L (mcg/L) most everywhere else. The two are numerically identical — 45 ng/mL is 45 µg/L. There's no conversion step, which makes ferritin unusually easy to compare across borders and across years of your own results. Only the reference interval changes, not the meaning of the unit.

Ferritin measures stored iron, not circulating iron

Ferritin is a hollow protein shell that packs iron away inside cells, mostly in the liver, spleen, and bone marrow. A small, proportional amount leaks into the bloodstream, and that leak is what the blood test picks up. The usual rule of thumb is that each 1 ng/mL corresponds to somewhere around 8–10 mg of stored iron, which is why a value of 12 and a value of 200 describe genuinely different reserves. How the storage protein works is a separate question from how much iron is moving through your blood right now.

That transport layer has its own tests. Serum iron, transferrin, and transferrin saturation (TSAT) describe iron in transit. Hemoglobin describes iron already built into red cells and doing its job. Three layers, three measurements, and they can move independently of each other.

Hemoglobin vs ferritin: why the two can disagree

Iron loss runs in a sequence. Stores drain first, so ferritin falls while everything else still looks fine. Then transport tightens — serum iron drops, TSAT falls, and the marrow starts running short. Only at the end does hemoglobin fall far enough to register as anemia, which WHO defines at roughly under 13 g/dL for men and under 12 g/dL for non-pregnant women.

A normal hemoglobin therefore doesn't rule out low ferritin. It's entirely ordinary to have depleted stores alongside a perfectly ordinary complete blood count — that combination is what "iron deficiency without anemia" names.

The reverse happens too. Anemia has causes that have nothing to do with iron, so ferritin can sit mid-range while hemoglobin is low because of B12, folate, kidney disease, or bleeding that hasn't yet drained the reserves. Neither test substitutes for the other, and neither is ordered as a replacement for the other.

Low ferritin: the most argued-over figure in the panel

There is no single agreed floor. WHO uses under 15 µg/L to define depleted iron stores in adults. Many clinicians work with a higher practical threshold — 30 ng/mL is common — on the reasoning that a person can run short of usable iron well before the number falls to 15. Some subspecialties argue for higher reference points still in particular contexts. Blood donors, endurance athletes, and people with heavy menstrual bleeding are all groups where the lab's printed lower bound and the clinical conversation routinely disagree.

None of that makes the reference interval wrong. It makes it a population statistic, read alongside symptoms, history, and the other results on the panel. A blog can print the bands; the person with your chart in front of them reads the result.

High ferritin: inflammation before overload

Ferritin is an acute-phase reactant — it rises with inflammation from any source. Infection, autoimmune flares, recent surgery, liver disease, heavy alcohol use, malignancy, and the chronic low-grade inflammation that travels with obesity and metabolic syndrome all push it upward. An elevated result is more often a marker of something inflammatory than a sign of excess iron.

It cuts the other way as well. Inflammation can lift ferritin into the normal band in someone whose stores are genuinely empty, which is the most common way a single value misleads. That's why CRP is frequently drawn alongside it — a normal CRP makes the ferritin easier to read at face value. WHO guidance notes that where infection or inflammation is present, a higher cutoff, around 70 µg/L, is the more appropriate one for judging depletion.

Real iron overload usually shows a second signal. Transferrin saturation climbing past about 45% alongside an elevated ferritin is the pattern that prompts evaluation for hereditary hemochromatosis; an elevated ferritin with a normal saturation points back more often at inflammation or the liver.

Where daily intake fits between blood draws

A blood test is a snapshot taken months apart. Between them, the iron variable you control directly is what you eat, and the reference point for that is the RDA rather than the lab interval. The NIH sets it at 8 mg a day for adult men and for women 51 and older, 18 mg for women 19–50, and 27 mg during pregnancy; people eating no meat are advised to aim for roughly 1.8 times those figures, since non-heme iron absorbs less efficiently. The full intake numbers by age and sex and which foods actually carry iron cover the practical side.

Writing that side down helps, because recall across a three-month gap is poor. Iron Tracker is an iron intake tracking app for iPhone, and a written record of daily mg between blood draws means the diet half of the picture isn't reconstructed from memory at the appointment.

FAQ

What is a good ferritin level?

Labs print a wide interval — roughly 24–336 ng/mL for men and 11–307 ng/mL for women — and there's no consensus point inside it that counts as ideal. A result near either edge means more when it's read with CRP, transferrin saturation, and hemoglobin next to it. That reading belongs to a clinician, not to a chart.

Can ferritin be normal and iron still be low?

Yes. Because ferritin rises with inflammation independently of stores, an infection, autoimmune flare, liver problem, or metabolic inflammation can lift the number into the normal band while reserves are empty. That's the main reason ferritin is often ordered together with CRP and transferrin saturation rather than on its own.

Does a high ferritin level mean too much iron?

Not usually. Inflammation, liver disease, and alcohol raise the number far more often than iron overload does. Genuine overload typically shows a raised transferrin saturation as well, and it's that combination — not the ferritin figure alone — that points toward conditions like hemochromatosis.

Is hemoglobin the same test as ferritin?

No. Hemoglobin measures iron already circulating in red blood cells; ferritin measures what's held in reserve in tissue. Stores drop first in the sequence, so ferritin can read low for months while hemoglobin still comes back normal.

How much does ferritin change day to day?

It drifts more than it swings, but it isn't stable. An infection can raise it within days, and it can stay elevated for some time after the illness resolves. Comparing a result drawn during an illness with one drawn afterward isn't comparing like with like.