Iron & Ferritin Status Calculator

Calculate your transferrin saturation from serum iron and TIBC, then interpret ferritin with sex-specific ranges and pattern recognition for iron deficiency, anemia of chronic disease, and iron overload.

Transferrin Saturation (TSAT) = (Serum Iron ÷ TIBC) × 100

Reference Ranges

Transferrin Saturation (TSAT)

< 20%Low
20 – 45%Normal
> 45%High

Ferritin — Male (ng/mL)

< 30Low
30 – 300Normal
> 300High

Ferritin — Female (ng/mL)

< 20Low
20 – 200Normal
> 200High

Combined Pattern Recognition

Low TSAT+Low FerritinIron Deficiency Anemia
Normal TSAT+Low FerritinDepleted Iron Stores
Low TSAT+Normal/High FerritinAnemia of Chronic Disease
High TSAT+High FerritinPossible Iron Overload
Normal TSAT+Normal FerritinAdequate Iron Status

Why Ferritin Alone Is Not Enough

Ferritin is the most commonly ordered iron marker, but it is also an acute-phase reactant — meaning it rises with inflammation, infection, liver disease, and metabolic syndrome, independent of true iron stores. A person with chronic inflammation can have a "normal" or even high ferritin while being functionally iron deficient.

The classic trap: A patient with rheumatoid arthritis, inflammatory bowel disease, or obesity may have ferritin of 80 ng/mL — technically normal — but a TSAT of 12%, signaling that iron is being sequestered by inflammation and is unavailable for red cell production. This is anemia of chronic disease, not iron deficiency, and the treatment is very different.

The full iron panel (serum iron, TIBC, transferrin saturation, and ferritin interpreted together) gives a far more accurate picture than any single marker alone.

Iron Deficiency Without Anemia

Iron deficiency exists on a spectrum. Long before hemoglobin drops and anemia appears on a CBC, iron stores can be exhausted. This pre-anemia stage — sometimes called iron depletion — causes real symptoms: fatigue, reduced exercise tolerance, brain fog, hair loss, restless legs, and cold intolerance.

Ferritin below 30 ng/mL in women (some practitioners use 50 ng/mL as the functional threshold) may warrant treatment even with a normal hemoglobin. Symptoms often resolve with iron supplementation before CBC values change.

Who is at highest risk: Premenopausal women (especially with heavy periods), vegetarians and vegans, endurance athletes, pregnant individuals, frequent blood donors, and people with celiac disease or inflammatory bowel disease.

When to Test the Full Iron Panel

A standard CBC flags low hemoglobin but does not tell you why. Requesting a complete iron panel — serum iron, TIBC, and ferritin — allows pattern-based diagnosis. If your ferritin is low or your TSAT is reduced, the next step is identifying the cause: inadequate intake, poor absorption (celiac, H. pylori), increased demand (pregnancy, growth), or blood loss (menstrual, GI).

Frequently Asked Questions

What is a normal ferritin level?
Reference ranges vary by sex. Males: 30-300 ng/mL. Females: 20-200 ng/mL. However, many functional medicine practitioners consider optimal ferritin to be 50-70 ng/mL or higher for symptom resolution.
What does transferrin saturation tell you?
It shows what percentage of your iron transport protein (transferrin) is loaded with iron. Below 20% suggests deficiency, 20-45% is normal, and above 45% raises concern for iron overload.
Can ferritin be high without iron overload?
Yes. Ferritin is an acute-phase reactant that rises with inflammation, infection, liver disease, obesity, and even vigorous exercise. Always check CRP alongside ferritin for context.
What are symptoms of iron deficiency before anemia?
Fatigue, hair loss, restless legs, brain fog, cold intolerance, brittle nails, and exercise intolerance can all appear when iron stores are depleted — well before hemoglobin drops below the anemia threshold.
Should I take iron supplements if my ferritin is low?
Discuss with your doctor first. The type of iron (ferrous sulfate vs bisglycinate), dose, timing (on empty stomach with vitamin C), and whether to investigate the cause of deficiency all matter.

Track iron labs over time and spot deficiency trends

Upload your lab results to Vitalix and see your ferritin and TSAT trend alongside symptoms, supplements, and dietary changes. AI flags patterns and tells you which tests to add next.

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This calculator is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider for interpretation of lab results and treatment decisions.