D-Dimer levels: what's normal, high and low
A fragment from broken-down clots. Used to rule out clotting disorders like DVT or pulmonary embolism.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
The short answer
D-Dimer is measured with a standard blood draw; no fasting is needed. A typical reference range is 0.000 – 500 ng/mL. At TestWell it's $69.99 all-in as D-Dimer, results in 1–3 business days, drawn at Quest or Labcorp. An out-of-range result is a prompt to look closer, not a diagnosis.
- Units
- ng/mL / mg/L FEU
- Sample
- Blood draw
- Fasting
- Not required
- Results
- 1–3 business days
- Price
- $69.99
- Labs
- Quest or Labcorp · BioReference in NY/NJ
D-Dimer Reference Range
These are the typical adult reference ranges used by major US labs. Your report will include the specific range used by the lab that processed your sample.
| Population | Range |
|---|---|
| age 18+ | 0.000 – 500 ng/mL |
Reference ranges are educational. Always interpret your result with the specific range printed on your lab report and discuss anything outside the range with a clinician.
Have a result in hand? analyze it with your AI assistant using these reviewed ranges, or run it through our explainer. Tools: look up another marker's range · convert lab units
What your D-Dimer result may mean
Often reflects active clotting and breakdown — DVT, PE, recent surgery, infection, pregnancy, or inflammation.
What a high D-Dimer means: causes, symptoms, next steps ↓Educational only — not a diagnosis. Many factors can influence a single result. Discuss anything that concerns you with a healthcare provider.
What does a high D-Dimer mean?
D-dimer is a fragment produced when a clot breaks down. It is raised by active clotting — deep-vein thrombosis, pulmonary embolism — but also by recent surgery or injury, infection, pregnancy, cancer, liver disease, and simply older age, so a high value is non-specific. A normal D-dimer in a low-risk person effectively rules a clot out; a high one needs clinical assessment and usually imaging, not a repeat test.
Common causes of a high D-Dimer
- Venous clot: DVT, pulmonary embolism
- Recent surgery, trauma, hospitalization
- Infection, inflammation, sepsis, COVID
- Pregnancy (rises through trimesters), cancer, liver disease
- Older age, heart disease, atrial fibrillation
Ordered from most to least common.
Symptoms that can go with it
- Calf pain, swelling, warmth (DVT)
- Sudden breathlessness, chest pain, rapid heart rate (PE)
- Often none when raised by age, surgery or illness
What clinicians usually check next
- Same-day clinical assessment if there are any clot symptoms — imaging (ultrasound or CT) decides
- Without symptoms: review recent surgery, infection, pregnancy; repeat in a few weeks
- CBC and kidney function
Follow-up tests at TestWell: CBC with Differential ($21.99).
Seek care promptly if
- Leg swelling with pain, or breathlessness/chest pain with a high D-dimer — emergency care
Can I use D-dimer to rule out a blood clot myself?
A normal result in a low-risk person is reassuring, but 'low risk' is a clinical judgement (Wells score). Any symptoms of a clot need same-day assessment regardless of the number.
Educational only — not a diagnosis. A single result outside the range is a prompt to look closer with a clinician.
How do you get a D-Dimer test?
Order online, a licensed physician reviews the requisition, and you walk into a nearby lab for the draw. D-Dimer is available on its own or inside these panels — panels cost less per marker when you want the fuller picture.
| Option | Includes | Price |
|---|---|---|
| D-Dimer | This marker only | $69.99 |
Quest vs. Labcorp for D-Dimer: which lab should you pick?
Both are CLIA-certified national labs and the result is clinically equivalent, so pick whichever location is closer. Your report will print that lab's own reference range, which can differ slightly from the table above.
| Lab | Available | Price |
|---|---|---|
| Quest Diagnostics | Yes | $69.99 |
| Labcorp | Yes | $69.99 |
| BioReference (NY & NJ) | Yes | $34.99 |
Need help choosing a location? Use the lab finder to see draw sites near your ZIP.
Frequently asked
What does a high D-Dimer mean?
D-dimer is a fragment produced when a clot breaks down. It is raised by active clotting — deep-vein thrombosis, pulmonary embolism — but also by recent surgery or injury, infection, pregnancy, cancer, liver disease, and simply older age, so a high value is non-specific. A normal D-dimer in a low-risk person effectively rules a clot out; a high one needs clinical assessment and usually imaging, not a repeat test.
Can I use D-dimer to rule out a blood clot myself?
A normal result in a low-risk person is reassuring, but 'low risk' is a clinical judgement (Wells score). Any symptoms of a clot need same-day assessment regardless of the number.
Do I need a doctor's order to test my d-dimer?
No. TestWell's licensed physician network reviews and approves your order — usually within minutes. You can place an order online without an in-person visit or a referral from your own doctor.
How long does it take to get D-Dimer results?
Most D-Dimer results are available in 1–3 business days after your specimen arrives at the lab. You'll get an email the moment your results are ready, with everything viewable in your TestWell portal.
How much does a D-Dimer test cost?
Our D-Dimer starts at $69.99. That's the all-in price — no copays, no insurance hoops, no surprise bills. HSA and FSA cards are accepted.
Do I need to fast before my D-Dimer test?
Fasting is not required for the D-Dimer test. You can have your blood drawn any time of day.
Which lab will process my D-Dimer test?
Your test will be processed by Quest Diagnostics, Labcorp, or BioReference depending on which is closest to you and which lab carries the test. All three are CLIA-certified and trusted by hospitals nationwide. You'll choose your lab during checkout from 4,000+ locations.
Ready to test your d-dimer?
Order in two minutes, get physician-approved, and visit a lab the same day. Starts at $69.99.