Coagulation Profile
These tests time the two arms of the clotting cascade. They are used before surgery, to monitor warfarin, and to investigate abnormal bleeding or clotting.
This is an educational reading aid, not a diagnosis and not medical advice. Reference ranges differ between laboratories — always read the range printed on your own report. Nothing here can see you, your history or your medicines. Do not start, stop or change any treatment on the strength of this page: take your report to a qualified doctor.
Reference ranges reviewed by Dr. Mohan Gayenlast reviewed
Your values
Fill in only the ones on your report. Anything you leave blank is simply skipped.
Times one arm of clotting. Prolonged by warfarin, liver disease and vitamin K deficiency.
The PT expressed so that any laboratory’s result means the same thing. About 1.0 in someone not on anticoagulants.
Times the other arm of clotting. Prolonged by heparin and by haemophilia.
The protein that forms the mesh of a clot. It also rises with inflammation.
A fragment released when a clot breaks down.
Enter one or more values and your reading will appear here.
What this panel is easy to get wrong
- PT and aPTT in seconds vary with the reagent the laboratory uses. INR exists precisely so that PT can be compared between laboratories.
- If you take warfarin or acenocoumarol, your INR target is set by your doctor and is usually 2.0–3.0 — a value inside that target is correct for you even though it is above the untreated range.
- D-dimer is useful mainly for RULING OUT clots in someone assessed as low risk. A raised D-dimer on its own does not mean a clot: infection, pregnancy, surgery, injury and older age all raise it.
Where these ranges come from: Commonly published adult intervals. INR targets follow standard anticoagulation practice; the target for an individual is set by their own doctor.
Where this is written from: This site is written from Indian clinical practice. Drug availability and brand names, vaccination schedules, national health programmes and some reference cut-offs differ between countries — a schedule or a threshold that is standard here may not be standard where you are. If you are reading outside India, check anything on this page against your own country’s guidance before you act on it.
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How quickly blood clots — PT, INR, aPTT, fibrinogen and D-dimer.