Platelet count optimal range and reference range
Compiled by Alina Radu, founder of Sera, from the published sources below · Last reviewed November 9, 2026
Sera's bands for Platelet count:
- Optimal 175 – 320 ×10⁹/L (175 – 320 ×10³/μL); sufficient 150 – 400 ×10⁹/L (150 – 400 ×10³/μL); out of range below 150 or above 400 ×10⁹/L.
Evidence grade: Published reference interval. A band that primarily reflects a published adult laboratory or population reference interval. It is not necessarily applicable to every assay or laboratory.
At Sera's last range review a change to this band was proposed and held, because the evidence for it was thin, so the band is unchanged. The note below says where it matches published intervals and where it does not.
All units
| Unit | Optimal | Sufficient | Out of range |
|---|---|---|---|
| ×10⁹/L | 175 – 320 | 150 – 400 | below 150 or above 400 |
| ×10³/μL | 175 – 320 | 150 – 400 | below 150 or above 400 |
| K/μL | 175 – 320 | 150 – 400 | below 150 or above 400 |
| /mm³ | 175,000 – 320,000 | 150,000 – 400,000 | below 150,000 or above 400,000 |
| x E9/L | 175 – 320 | 150 – 400 | below 150 or above 400 |
What the evidence says
The acceptable band of 150 to 400 ×10⁹/L is the conventional adult reference interval, as given by MedlinePlus. The optimal lower edge of 175 matches a Danish cohort of 21,252 adults in which mortality was higher below it; the same cohort found higher mortality above 300, where the optimal band here runs to 320.
Sources
- Platelet count — MedlinePlus Medical Encyclopedia, U.S. National Library of Medicine, 2025 · Government / public-health guidanceNormal adult platelet count is 150,000 to 400,000 per microlitre, or 150 to 400 ×10⁹/L. This matches Sera's sufficient band exactly.
- Platelet count is associated with cardiovascular disease, cancer and mortality: A population-based cohort study — Vinholt PJ, Hvas AM, Frederiksen H, et al. — Thrombosis Research, 2016 · Peer-reviewed publicationDanish general-population cohort of 21,252 adults. Against a reference group of 201 to 250 ×10⁹/L, mortality was higher below 175 and above 300. Supports the optimal lower edge of 175 and an upper edge of 300 rather than 320.
- Complete Blood Cell Count (CBC) with Differential, Blood (Test ID CBC) — Mayo Clinic Laboratories, 2026 · Laboratory / reference-interval sourceAdult platelet reference values are 135 to 317 ×10⁹/L in men and 157 to 371 in women. A sex-specific interval that is narrower than Sera's sufficient band at the top.
- Haematology reference ranges — Gloucestershire Hospitals NHS Foundation Trust, 2026 · Laboratory / reference-interval sourceAdult platelet count 140 to 400 ×10⁹/L. Supports the sufficient upper edge of 400.
What Platelets (Thrombocytes) measures
Tiny blood cells that help your blood clot.
Can be affected by autoimmune conditions and infections. Part of a full blood assessment.
Related blood cell health markers
- RBC # (Red Blood Cell Count)
- Hemoglobin (HGB)
- Hematocrit (HCT)
- Mean Corpuscular Volume (MCV)
- Mean Corpuscular Hemoglobin (MCH)
- Mean Corpuscular Hemoglobin Concentration (MCHC)
- RDW (Red Cell Distribution Width)
- WBC # (White Blood Cell Count)
- Neutrophils #
- Lymphocytes #
- Monocytes #
- Eosinophils #
- Basophils #
- Neutrophils %
- Lymphocytes %
- Monocytes %
- Eosinophils %
- Basophils %
- Immature Granulocytes %
- PCT (Plateletcrit)
- Reticulocytes (Absolute)
- Reticulocytes (%)
- Ferritin
- Iron (Serum)
- Transferrin
- TIBC (Total Iron Binding Capacity)
- Transferrin Saturation
- UIBC (Unsaturated Iron Binding Capacity)