Is my Platelets normal?
Free blood test checker · Standard + longevity-optimal ranges
What is a normal Platelets level?
Platelets are small blood cells that form clots to stop bleeding. Normal count is 150-400 K/µL (thousands per microliter). Low platelets (thrombocytopenia) increase bleeding risk. High platelets (thrombocytosis) can indicate inflammation, infection, or rarely a blood disorder. Platelets are part of every CBC panel.
| Range | Values |
|---|---|
| Standard Reference | 150–400 K/µL |
| High Risk | > 500 K/µL |
| Low Risk | < 100 K/µL |
What causes abnormal Platelets levels?
Low platelets (thrombocytopenia) are caused by decreased production (bone marrow disorders, chemotherapy, B12/folate deficiency), increased destruction (immune thrombocytopenia, TTP, HUS, medications like heparin), and sequestration (enlarged spleen from liver disease). High platelets (thrombocytosis) are caused by reactive conditions (infection, inflammation, iron deficiency, post-surgery, post-splenectomy) or primary bone marrow disorders (essential thrombocythemia, polycythemia vera).
When should you see a doctor?
See your doctor if platelets are below 100 K/µL (increased bleeding risk) or above 500 K/µL. Seek urgent care if below 50 K/µL (significant bleeding risk) or if you notice unexplained bruising, petechiae (tiny red spots), nosebleeds, or prolonged bleeding from cuts.
Platelets and longevity
Platelet count is a basic but important marker in the longevity context. Mean platelet volume (MPV), which measures platelet size, is emerging as a more nuanced marker — larger platelets are more metabolically active and prothrombotic, and elevated MPV is associated with increased cardiovascular event risk independently of platelet count. Chronic low-grade thrombocytosis (mildly elevated platelets, 400-500 K/µL) is most commonly reactive — driven by iron deficiency, chronic inflammation, or infection — rather than a primary bone marrow disorder. In aging populations, a gradually declining platelet count should prompt evaluation of bone marrow reserve and nutritional status (B12, folate). Aspirin therapy, which inhibits platelet aggregation, remains one of the most studied longevity interventions, though its benefit-risk ratio is now considered nuanced outside of secondary prevention.
Where to get a Platelets test
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Related biomarkers
These biomarkers are often tested alongside Platelets for a more complete picture.
Frequently asked questions
What is a normal platelet count?
What causes low platelets?
What causes high platelets?
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Sources: Reference ranges based on AHA/ACC, ADA, and AACE clinical guidelines. Biological variation data from Ricos/Westgard database. Longevity-optimal ranges reflect targets used by preventive and functional medicine practitioners.
Last reviewed: April 2026. This tool provides general health information and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider about your specific results.