Eosinophil Count Calculator

What Is the Absolute Eosinophil Count?

The absolute eosinophil count (AEC) estimates how many eosinophils are present in a blood sample. Eosinophils are white blood cells involved in allergic responses and defense against certain parasites. Clinicians use AEC alongside the complete blood count (CBC) to track allergy, asthma, infection, and some hematologic conditions.

How to Calculate AEC

After a CBC reports white blood cell count (WBC) and eosinophil percentage (EOS%), apply:

$$AEC = WBC \times \frac{EOS\%}{100}$$

When WBC is entered in ×10³/μL, the result is also in ×10³/μL. That unit is equivalent to ×10⁹/L. For example, WBC 7.2 ×10³/μL with 3% eosinophils gives AEC 0.216 ×10³/μL, or 216 cells/μL.

Reference Ranges and Interpretation

Typical adult reference interval is 0.04 to 0.45 ×10³/μL. Values above 0.45 suggest eosinophilia, often linked to allergy, asthma, or parasitic infection. Values above 1.5 ×10³/μL indicate hypereosinophilia and may need further workup. Values below 0.04 suggest eosinopenia, which can occur with acute stress, corticosteroid use, or acute infection.

Related hematology tools include the ANC Calculator for neutrophil counts and other CBC-based calculators on OnlineMiniTools.