Hemostasis D-dimer FEU / DDU

D-dimer Unit Converter

Convert D-dimer between FEU and DDU units, including ng/mL, µg/L, mg/L, µg/mL, and ng/L.

Published on: 2026-06-08 · Last updated: 2026-06-08

Enter D-dimer value

You can enter a value in any supported unit.
Please enter a valid positive number.

What does this converter do?

This tool converts D-dimer values between FEU and DDU reporting systems and between common concentration units such as ng/mL, µg/L, mg/L, µg/mL and ng/L. It is designed for laboratory unit conversion only. It does not apply age-adjusted D-dimer rules and does not interpret whether a result is positive or negative.

Supported units

ng/mL FEU µg/L FEU mg/L FEU µg/mL FEU ng/L FEU ng/mL DDU µg/L DDU mg/L DDU µg/mL DDU ng/L DDU

Conversion formulas

ng/mL FEU = µg/L FEU
mg/L FEU = µg/mL FEU
1 mg/L FEU = 1000 ng/mL FEU
ng/mL DDU = µg/L DDU
mg/L DDU = µg/mL DDU
1 mg/L DDU = 1000 ng/mL DDU
FEU ≈ DDU × 2
DDU ≈ FEU ÷ 2

Important notes about D-dimer units

D-dimer reporting is not standardized across all laboratories. The most important distinction is whether the result is reported as FEU or DDU. Always check the unit type printed on the laboratory report before comparing a result with a clinical threshold.

  • FEU means fibrinogen equivalent units. Many clinical algorithms and common cutoffs are expressed in FEU.
  • DDU means D-dimer units. For the same specimen, DDU values are usually about half of FEU values.
  • 500 ng/mL FEU is approximately equivalent to 250 ng/mL DDU.
  • ng/mL and µg/L are numerically equivalent for D-dimer concentration.
  • mg/L and µg/mL are numerically equivalent.
  • A unit such as “500” is not interpretable unless the report states both the concentration unit and whether it is FEU or DDU.

Example conversion

If D-dimer = 500 ng/mL FEU, then it is equivalent to 500 µg/L FEU, 0.50 mg/L FEU, 0.50 µg/mL FEU, and approximately 250 ng/mL DDU.

Important laboratory note

D-dimer interpretation depends on the clinical situation, pretest probability, assay method, reporting unit, age, pregnancy, recent surgery, infection, inflammation, cancer, liver disease, anticoagulant use and local laboratory cutoff. This converter only changes units and does not diagnose pulmonary embolism, deep vein thrombosis, disseminated intravascular coagulation or any thrombotic condition.