Ferritin µg/L to ng/mL: the same number

The short answer

There is nothing to convert. 1 µg/L is exactly 1 ng/mL, so a ferritin of 30 µg/L is 30 ng/mL. ug/L and mcg/L are the same unit written without the Greek µ. Only pmol/L, which a few labs use, gives a different number: multiply µg/L by about 2.25.

A microgram is 1,000 nanograms, and a litre is 1,000 millilitres. The two thousands cancel out, so micrograms per litre and nanograms per millilitre describe exactly the same amount of ferritin in your blood.

µg/L30Ferritin as many European labs print it
ng/mL30The same result as many US labs print it
pmol/L67The same result in the unit a few labs use

Common ferritin results in each unit

µg/L (ug/L, mcg/L)	ng/mL	pmol/L	What it usually means
15	15	34	Stores are empty. See your doctor.
30	30	67	Below this, stores count as depleted.
50	50	112	Where the guide's goal starts.
80	80	180	The top of the guide's goal.
100	100	225	Inside most lab ranges for women.
150	150	337	Above many lab ranges for women. A question for your doctor.

The ways labs write it

µg/L, ug/L, mcg/L: micrograms per litre, three spellings of one unit.
ng/mL: nanograms per millilitre, the same number as µg/L.
pmol/L: picomoles per litre. Divide by about 2.25 to get µg/L, so 67 pmol/L is about 30 µg/L.

If a result says µg/dL or µmol/L, it is almost certainly serum iron, not ferritin. That is a different test with different numbers: see ferritin vs serum iron.

Convert any marker

The unit tells you nothing about whether a result is good. For that, read it against your lab's range and the guide's goal of 50 to 80 µg/L: see ferritin levels.

Questions

Is 30 ng/mL the same as 30 µg/L?

Yes. For ferritin, ng/mL and µg/L are the same unit in different sizes, so the number does not change.

Is ug/L the same as µg/L?

Yes. ug is µg typed without the Greek letter µ, and mcg is another way to write it. All three mean micrograms.

How do I convert ferritin from pmol/L to µg/L?

Divide by about 2.25 (2.247). A ferritin of 67 pmol/L is about 30 µg/L, and 112 pmol/L is about 50 µg/L.

Why do labs use different units?

Countries follow different conventions. The number only changes in pmol/L; between µg/L and ng/mL it stays the same, so you can compare results from either directly, as long as they come from the same lab.

Sources

This page has not been reviewed by a clinician yet. Read it as general education, and take your own results to your doctor.

Educational, not medical advice. ferritin.ai does not diagnose or treat any condition, and it never sets a dose. Talk to your doctor about your own results.