INR Calculator

Calculate INR (International Normalized Ratio) from PT. Assess anticoagulation status and warfarin therapy monitoring. This is an educational tool only - always consult a healthcare provider.

Laboratory Values

Typical range: 0.9-1.7 (varies by reagent)

Results

Enter lab values to calculate INR

About INR

  • • INR = (PT/Control PT)^ISI
  • • Normal: 0.9-1.1
  • • Warfarin target: 2.0-3.0
  • • Mechanical valve: 2.5-3.5