Can this result diagnose a condition on its own?

No. A laboratory result should be interpreted with related tests, symptoms, medical history, and the reference information on the report.

Which reference range should I use?

Use the reference interval provided by the laboratory that performed the test. Clinical decision cutoffs, when relevant, are shown separately.

When should I discuss the result with a healthcare professional?

Professional assessment is appropriate when a result is markedly outside the reference interval, serious symptoms are present, an abnormality persists or recurs, or follow-up has been recommended.

Information about a laboratory test

Basophils: What Does This Blood Test Measure?

Shows the percentage or absolute number of basophils, white blood cells involved in allergic responses and inflammation.

Test summary

Test name: Basophils
Abbreviations: BASO
Category: Hematology / Immunology
Panel: WBC Differential / Hemogram
Specimen: Whole blood
Common units: %, /µL, x10^9/L

What does the test measure?

Shows the percentage or absolute number of basophils, white blood cells involved in allergic responses and inflammation.

Why is the test ordered?

Measured as part of the white blood cell differential and usually interpreted together with changes in other white-cell types.

Information about a low result

A low basophil result is often not clinically meaningful by itself.

Information about a high result

A high basophil result can occur in some allergic or inflammatory conditions and in certain hematologic disorders.

Reference and clinical context

Use the reference interval printed on your own laboratory report first. Reference intervals may vary by laboratory, method, unit, age, sex, pregnancy, specimen, and other conditions. Numeric records in this workbook are explicitly labeled as either source-based example reference intervals or clinical decision cutoffs.

Reference range 1

>= 0.5 – <= 1 %

Population: General
Specimen: Whole blood

Example differential percentage

MedlinePlus example differential percentage; absolute counts and lab-specific ranges may be more relevant.

Reference ranges may vary by laboratory, method used, age, sex, pregnancy status, and clinical context. The reference range on your own laboratory report takes precedence.

Interpretation notes

Basophils are a relatively uncommon white-cell subtype; percentage changes should be considered with the total WBC count and other differential values.

Related specialties

Hematology
Allergy and Immunology
Internal Medicine

Frequently asked questions

Sources

Blood Differential — U.S. National Library of Medicine (MedlinePlus)
Government medical reference · 2024 · Neutrophil, lymphocyte, monocyte, eosinophil, basophil roles and example percentages · Verified: Aug 11, 2026