The short answer
Platelets are tiny cell fragments that plug leaks in your blood vessels, and your platelet count is how many you have. A normal count is 150 to 450 ×10³/µL. Too few, and you can bruise and bleed more easily; too many is usually your body reacting to something else, such as an infection or low iron.2,6
- A healthy range
- 150 to 450 ×10³/µL. Platelets can dip for a while after a viral infection, so a mildly low result is often worth repeating.1
Check your result
Type the number from your report. It stays on this page.
- Severely low Under 20
- Very low 20 to 49
- Low 50 to 99
- Mildly low 100 to 149
- Normal 150 to 450
- High 451 to 999
- Very high 1,000 or more
Enter your result to see what it means and what to do next.
Got a result from another lab? Ask Picardo about it. The app explains your results, and a physician can follow up.
Green is Labcorp’s normal range. The 20 and 50 lines come from guidance on bleeding risk and surgery,1,3 100 from the definition of immune thrombocytopenia,4 450 from the criteria for essential thrombocythemia5 and 1,000 from the definition of extreme thrombocytosis.7 The bar isn’t to scale.
Severely low: get care today
At this level, the risk of serious bleeding rises.1 Many people still have only bruises or tiny red spots on the skin, but bleeding from the gut, in the urine or, rarely, in the brain can happen.2 If this is new and turns out to be immune thrombocytopenia (ITP), US guidelines suggest starting care in hospital.3
Get medical care today. Go to the emergency department now if you have bleeding that won’t stop, blood in your urine, stool or vomit, a sudden severe headache or changes in your vision.2,4
- 1 Contact a clinician today. If you can’t be seen today, go to the emergency department.1
- 2 Expect a repeat count and a look at your blood under a microscope (a blood smear). That also rules out platelets clumping in the tube, which can make a count read falsely low.1
- 3 Until you’re seen, avoid over-the-counter pain relievers such as ibuprofen, naproxen and aspirin. In people with ITP, they go with more bleeding.1
- 4 If you take a blood thinner or aspirin on prescription, call the clinician who prescribes it today rather than stopping it on your own. Blood thinners also go with more bleeding at low counts.1
Very low: see a clinician within days
Low enough that the cause needs finding quickly. Bleeding risk is lower than under 20,1 but if this turns out to be newly diagnosed ITP, US guidelines suggest treatment under 30.3 Under 50, most surgery and complex dental work would wait until the count is higher.1
See a clinician in the next few days. Go to the emergency department for bleeding that won’t stop or a sudden severe headache, or if you see blood in your urine, stool or vomit.2,4
- 1 See a clinician within a few days. If it turns out to be ITP, US guidelines advise seeing a hematologist quickly after the diagnosis.2
- 2 Expect a repeat count and a blood smear, which also rules out clumping in the tube.1
- 3 Avoid over-the-counter ibuprofen, naproxen and aspirin unless a clinician says otherwise. Don’t stop prescribed aspirin or a blood thinner without asking the clinician who prescribes it.1
- 4 Tell any dentist or surgeon your count before a procedure.1
Low: worth finding the cause
Clearly below normal, though not low enough to raise your bleeding risk much on its own.1 Under 100 is the line used to define ITP, where your immune system clears platelets,4 but ITP is only diagnosed once other causes, from medicines to liver disease, are ruled out.1
Not an emergency. See a clinician in the next week or two, and sooner if you notice new bruising or bleeding.
- 1 Ask for a repeat count and a blood smear, which also shows whether platelets clumped in the tube.1
- 2 Go over alcohol, recent infections and any medicines with your clinician, including quinine, the bitter ingredient in tonic water.1
- 3 If you’re pregnant, a count under 100 is lower than pregnancy alone usually causes, so other causes need checking.1
- 4 Tell your surgeon or dentist before any procedure. For major surgery, clinicians usually want a count of at least 80.1
Mildly low: often harmless, worth a repeat
Just under the lab’s range. A recent viral infection can cause a temporary dip, and alcohol and some medicines can lower the count too. In pregnancy, about 1 in 10 women have a count under 150 when they give birth.1 The count can also read falsely low if platelets clump together in the tube.1
Usually not a worry if you feel well and the rest of your blood count is normal.
- 1 Repeat the count, after you’ve recovered if you’ve recently been ill.1
- 2 If it’s still low, a blood smear can check for clumping in the tube.1
- 3 See a clinician if your red or white cells are also abnormal, if the count keeps falling or if you bruise or bleed easily.1,2
In the normal range
Your count is in Labcorp’s normal range. That rules out a platelet shortage, though not every bleeding problem; platelets that don’t work properly, or a clotting problem, can cause easy bleeding with a normal count.1
Nothing to worry about.
- 1 Nothing to do about your platelets.
- 2 If you bruise or bleed easily anyway, mention it to a clinician.1
High: usually a reaction to something else
Most high counts are reactive. Your bone marrow makes extra platelets because of something else, most often recovery from surgery or an injury, an infection, inflammation or low iron.6 Reactive counts rarely cause clots unless you have other risks.6 Less often, the marrow itself overproduces, as in essential thrombocythemia, where a count of 450 or more is the first criterion.5 In people 40 and older, a high count is also linked with a higher chance of cancer, mostly lung and bowel cancer.8
Not urgent, but don’t ignore it if it stays high. See a clinician in the next few weeks.
- 1 Repeat the count once you’ve recovered from any recent illness, injury or surgery.
- 2 Check iron, ferritin and CRP for the common causes: low iron and inflammation.6
- 3 If you’re 40 or older and there’s no clear cause, ask a clinician about checking for cancer.8
- 4 If it stays high with no cause found, ask about a blood test for the JAK2, CALR and MPL gene changes behind essential thrombocythemia.5
Very high: see a clinician soon
This is called extreme thrombocytosis. It’s still most often reactive: in a study of 280 hospital patients with counts this high, 82% had a reactive cause and 14% had a bone marrow disease.7 Marrow causes are the ones that more often lead to clots or bleeding, so the cause needs finding soon.6,7
Book an appointment within the next week or two.
- 1 Take this result to a clinician, with iron, ferritin and CRP results if you can.5
- 2 Tell them about any recent surgery, injury or infection, which are common reactive causes.6
- 3 Ask about a blood test for the JAK2, CALR and MPL gene changes, which point to a marrow cause.5
What is a normal platelet count?
Labcorp calls 150 to 450 ×10³/µL normal. Outside that range, how much a result matters depends on how far out it is, and on whether you have symptoms such as unusual bleeding.1 These are the lines clinicians use:
Severely low: get care today
At this level, the risk of serious bleeding rises.1 Many people still have only bruises or tiny red spots on the skin, but bleeding from the gut, in the urine or, rarely, in the brain can happen.2 If this is new and turns out to be immune thrombocytopenia (ITP), US guidelines suggest starting care in hospital.3
Get medical care today. Go to the emergency department now if you have bleeding that won’t stop, blood in your urine, stool or vomit, a sudden severe headache or changes in your vision.2,4
- 1 Contact a clinician today. If you can’t be seen today, go to the emergency department.1
- 2 Expect a repeat count and a look at your blood under a microscope (a blood smear). That also rules out platelets clumping in the tube, which can make a count read falsely low.1
- 3 Until you’re seen, avoid over-the-counter pain relievers such as ibuprofen, naproxen and aspirin. In people with ITP, they go with more bleeding.1
- 4 If you take a blood thinner or aspirin on prescription, call the clinician who prescribes it today rather than stopping it on your own. Blood thinners also go with more bleeding at low counts.1
Very low: see a clinician within days
Low enough that the cause needs finding quickly. Bleeding risk is lower than under 20,1 but if this turns out to be newly diagnosed ITP, US guidelines suggest treatment under 30.3 Under 50, most surgery and complex dental work would wait until the count is higher.1
See a clinician in the next few days. Go to the emergency department for bleeding that won’t stop or a sudden severe headache, or if you see blood in your urine, stool or vomit.2,4
- 1 See a clinician within a few days. If it turns out to be ITP, US guidelines advise seeing a hematologist quickly after the diagnosis.2
- 2 Expect a repeat count and a blood smear, which also rules out clumping in the tube.1
- 3 Avoid over-the-counter ibuprofen, naproxen and aspirin unless a clinician says otherwise. Don’t stop prescribed aspirin or a blood thinner without asking the clinician who prescribes it.1
- 4 Tell any dentist or surgeon your count before a procedure.1
Low: worth finding the cause
Clearly below normal, though not low enough to raise your bleeding risk much on its own.1 Under 100 is the line used to define ITP, where your immune system clears platelets,4 but ITP is only diagnosed once other causes, from medicines to liver disease, are ruled out.1
Not an emergency. See a clinician in the next week or two, and sooner if you notice new bruising or bleeding.
- 1 Ask for a repeat count and a blood smear, which also shows whether platelets clumped in the tube.1
- 2 Go over alcohol, recent infections and any medicines with your clinician, including quinine, the bitter ingredient in tonic water.1
- 3 If you’re pregnant, a count under 100 is lower than pregnancy alone usually causes, so other causes need checking.1
- 4 Tell your surgeon or dentist before any procedure. For major surgery, clinicians usually want a count of at least 80.1
Mildly low: often harmless, worth a repeat
Just under the lab’s range. A recent viral infection can cause a temporary dip, and alcohol and some medicines can lower the count too. In pregnancy, about 1 in 10 women have a count under 150 when they give birth.1 The count can also read falsely low if platelets clump together in the tube.1
Usually not a worry if you feel well and the rest of your blood count is normal.
In the normal range
Your count is in Labcorp’s normal range. That rules out a platelet shortage, though not every bleeding problem; platelets that don’t work properly, or a clotting problem, can cause easy bleeding with a normal count.1
Nothing to worry about.
- 1 Nothing to do about your platelets.
- 2 If you bruise or bleed easily anyway, mention it to a clinician.1
High: usually a reaction to something else
Most high counts are reactive. Your bone marrow makes extra platelets because of something else, most often recovery from surgery or an injury, an infection, inflammation or low iron.6 Reactive counts rarely cause clots unless you have other risks.6 Less often, the marrow itself overproduces, as in essential thrombocythemia, where a count of 450 or more is the first criterion.5 In people 40 and older, a high count is also linked with a higher chance of cancer, mostly lung and bowel cancer.8
Not urgent, but don’t ignore it if it stays high. See a clinician in the next few weeks.
- 1 Repeat the count once you’ve recovered from any recent illness, injury or surgery.
- 2 Check iron, ferritin and CRP for the common causes: low iron and inflammation.6
- 3 If you’re 40 or older and there’s no clear cause, ask a clinician about checking for cancer.8
- 4 If it stays high with no cause found, ask about a blood test for the JAK2, CALR and MPL gene changes behind essential thrombocythemia.5
Very high: see a clinician soon
This is called extreme thrombocytosis. It’s still most often reactive: in a study of 280 hospital patients with counts this high, 82% had a reactive cause and 14% had a bone marrow disease.7 Marrow causes are the ones that more often lead to clots or bleeding, so the cause needs finding soon.6,7
Book an appointment within the next week or two.
What are platelets?
Think of platelets as a repair crew in your blood. When a blood vessel is nicked, they rush to the spot, stick together to plug the hole and help a clot form over it.
Your bone marrow makes platelets all the time. A count of 150 to 450 ×10³/µL means 150,000 to 450,000 platelets in each microliter of blood.
With too few, you bruise more easily and may notice tiny red or purple spots on your skin, nosebleeds or heavy periods.2 Too many is usually a sign of something else going on, such as an infection or low iron, rather than a problem in itself.6,7
What causes a low platelet count?
Low platelets have many possible causes:1
- Platelets clumping in the test tube, which makes the count read falsely low (pseudothrombocytopenia)
- A recent viral infection, which usually causes only a temporary dip
- Pregnancy, especially near the due date
- Alcohol, and quinine, the bitter ingredient in tonic water
- Medicines, including heparin, valproate and chemotherapy
- Liver disease or an enlarged spleen
- Severe B12 or folate deficiency
- Immune thrombocytopenia (ITP), where your immune system destroys platelets and slows their production3
- HIV or hepatitis C, which can look just like ITP
- Less often, bone marrow diseases such as leukemia, or an inherited condition
ITP is uncommon: estimates of new cases range from 1 to 6 per 100,000 adults.3 It’s diagnosed only once other causes are ruled out, because no single test confirms it.1
What causes a high platelet count?
Most high counts are reactive: the bone marrow makes extra platelets in response to something else. In a German hospital study of counts of 500 or more, nearly 9 in 10 had a reactive cause.6 The usual causes are:6
- Tissue damage, such as after surgery or an injury
- Infection
- Low iron
- Long-term inflammatory diseases
- Cancer
- Some medicines, and having had your spleen removed
Less often, the marrow itself is the cause, as in essential thrombocythemia.5 Marrow-driven counts tend to be higher and are the ones linked with blood clots. Reactive counts rarely cause clots unless you have other risks.6
In adults 40 and older, a high count can also be a sign of cancer. In a large UK study, about a third of people whose high count turned out to be lung or bowel cancer had no other symptoms of it.8
How to raise a low platelet count
What raises the count is treating the cause:1
- Stopping or switching a medicine that lowers platelets, with your clinician’s help
- Cutting down on alcohol
- Treating low B12 or folate
- Treating HIV or hepatitis C, which can bring the count back to normal
- Waiting out a viral infection, since the dip usually passes
For ITP, the goal isn’t a normal count. It’s keeping the count high enough to prevent serious bleeding, usually above 20 to 30.1 If you’re newly diagnosed and have no more than minor bleeding, such as bruises, US guidelines suggest treatment under 30 and recommend watching rather than treating at 30 or more.2,3
The 2026 update to those guidelines kept that threshold but changed the first treatment. It now suggests steroids plus either rituximab or a medicine that makes the marrow produce more platelets, rather than steroids alone. That’s a conditional recommendation, based on low-certainty evidence.3
If more treatment is needed, the guidelines’ firm first choice is a platelet-boosting medicine such as eltrombopag or romiplostim, with rituximab as the alternative.3 Rilzabrutinib, a newer kind of medicine called a BTK inhibitor, was approved for ITP in 2025. The guidelines suggest it, alongside two other options, for people who can’t have or don’t want those.3
Who should get a platelet count?
A platelet count comes with every complete blood count, so you may already have one. It’s worth checking if any of these apply to you:
- You bruise easily, or get tiny red or purple spots on your skin, nosebleeds or heavy periods.2
- You drink heavily, or have liver disease, HIV or hepatitis C.1
- You’re pregnant.1
- You have surgery or dental work coming up and have had a low count before.1
- You have a long-term inflammatory disease or low iron, which can push the count up.6
- A past result was out of range and you want to see whether it has moved.
How to get a platelet count test, and what it costs
It comes from the complete blood count, which costs $3.75 through Picardo.
Complete blood count
The test this number comes from.
- Results in 2 to 3 days, in the app
- Physician follow-up if you want one
- Free Labcorp draw, or $75 at home
- No other fees. HSA and FSA eligible.
It’s also part of the Base Core Annual – Men, Base Core Annual – Women, Heart Health, Brain Health Screening, Pregnancy, Postpartum, Fertility, Thyroid & Autoimmunity and Celiac / GI panels, if you’d rather test more at once.
Already have a result? Ask Picardo about itQuestions people ask
What platelet count is dangerous?
There’s no single cutoff. Bleeding risk rises under 20,1 and in ITP, clinicians aim for at least 50 before minor surgery and 80 before major surgery.1 But bleeding varies a lot from person to person and doesn’t track the count closely, so symptoms matter as much as the number.1,2 At the high end, counts matter most when the cause is a bone marrow disease.6,7
Can a high platelet count mean cancer?
Sometimes, in older adults. In a UK study of people 40 and older tested by their family doctor, 6.2% of women and 11.6% of men with a count over 400 were diagnosed with cancer within a year, against 2.2% and 4.1% of those with a normal count. A second high count within six months raised that to 10.1% and 18.1%. Lung and bowel cancer were the most common.8 Their median age was 68, so the numbers don’t apply directly to a younger, healthy person. This is an observational link, and most people with a high count don’t have cancer.6,8
Does pregnancy lower your platelet count?
Yes, a little. Counts fall by about 10% in the second half of pregnancy, and about 1 in 10 women have a count under 150 when they give birth. A count under 100 is much rarer, at about 1 in 100, and is worth checking for other causes.1
Should I avoid ibuprofen or aspirin if my platelets are low?
If your count is well below normal, ask a clinician first. In people with ITP, blood thinners and anti-inflammatory pain relievers such as ibuprofen and aspirin go with more bleeding.1 Don’t stop a prescribed blood thinner without talking to the clinician who prescribes it.
What is essential thrombocythemia?
A bone marrow disease in which the marrow makes too many platelets. Diagnosis needs a count of 450 or more, a bone marrow biopsy and either a change in the JAK2, CALR or MPL gene or other signs that the count isn’t reactive.5 High counts driven by the marrow are more often linked with blood clots than reactive ones.6 In August 2026, the FDA approved ropeginterferon alfa-2b (Besremi), an interferon injection, for adults with it.9
Often checked alongside
Test details
- Labcorp test
- Complete Blood Count (CBC) With Differential, Reflex to Peripheral Smear Review, 005009
- LOINC
- 777-3
- Sample
- Blood
- Fasting
- Not needed
- Typical lab range
- 150 to 450 ×10³/µL
- Units
- ×10³/µL, which Labcorp prints as x10E3/uL. It’s the same number as ×10⁹/L.
Sources
- 1 Provan D, Arnold DM, Bussel JB, et al. Updated international consensus report on the investigation and management of primary immune thrombocytopenia. Blood Adv. 2019;3(22):3780–3817. doi.org/10.1182/bloodadvances.2019000812
- 2 Neunert C, Terrell DR, Arnold DM, et al. American Society of Hematology 2019 guidelines for immune thrombocytopenia. Blood Adv. 2019;3(23):3829–3866. doi.org/10.1182/bloodadvances.2019000966
- 3 Cuker A, Terrell DR, Sowdagar H, et al. American Society of Hematology 2026 guidelines for immune thrombocytopenia: initial and second-line therapy for adults with primary ITP. Blood Adv. 2026;10(20):7076–7097. doi.org/10.1182/bloodadvances.2026021269
- 4 Chowdhury SR, Sirotich E, Guyatt G, et al. Guideline on the emergency management of critical bleeding in patients with immune thrombocytopenia. Blood Adv. 2026;10(16):5558–5575. doi.org/10.1182/bloodadvances.2025018818
- 5 Arber DA, Orazi A, Hasserjian RP, et al. International Consensus Classification of myeloid neoplasms and acute leukemias: integrating morphologic, clinical, and genomic data. Blood. 2022;140(11):1200–1228. doi.org/10.1182/blood.2022015850
- 6 Griesshammer M, Bangerter M, Sauer T, Wennauer R, Bergmann L, Heimpel H. Aetiology and clinical significance of thrombocytosis: analysis of 732 patients with an elevated platelet count. J Intern Med. 1999;245(3):295–300. doi.org/10.1046/j.1365-2796.1999.00452.x
- 7 Buss DH, Cashell AW, O’Connor ML, Richards F 2nd, Case LD. Occurrence, etiology, and clinical significance of extreme thrombocytosis: a study of 280 cases. Am J Med. 1994;96(3):247–253. doi.org/10.1016/0002-9343(94)90150-3
- 8 Bailey SE, Ukoumunne OC, Shephard EA, Hamilton W. Clinical relevance of thrombocytosis in primary care: a prospective cohort study of cancer incidence using English electronic medical records and cancer registry data. Br J Gen Pract. 2017;67(659):e405–e413. doi.org/10.3399/bjgp17X691109
- 9 PharmaEssentia. BESREMi (ropeginterferon alfa-2b-njft) injection: prescribing information. Revised August 2026. DailyMed. Accessed October 28, 2026. dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=9583405d-53a0-49dc-88eb-5e6384ebabcb
Updated 28 Oct 2026.
This is general health information, not medical advice: talk to your clinician about your results and before changing any treatment.