INR Calculator

Calculate INR or solve for PT / Control / ISI — live sync

Live
Inputs
Pick which field is calculated automatically.
Prothrombin time for the patient.
Your lab’s mean normal PT.
Unitless; typically around 0.9–1.7.
Formula: INR = (PTpatient / PTcontrol)ISI
Result
INR
Enter values to calculate.
Educational use only — not medical advice. Follow clinical guidance.

More of our calculators...

Waist to Hip and Height Ratio Calculator

Calculate waist-to-hip and waist-to-height ratios. Check health risk ranges with quick measurements and results.

Maintenance Calorie Calculator

Calculate maintenance calories (TDEE) from BMR and activity. Know how many calories to maintain your current weight.

Harris-Benedict Calculator (Basal Metabolic Rate)

Use the Harris-Benedict equation to calculate BMR and estimate daily calories (TDEE) based on activity level.

BMR — Basal Metabolic Rate (Mifflin–St Jeor)

Calculate BMR using the Mifflin-St Jeor equation. Get your daily calorie needs based on age, height, weight, and sex.

Weight Gain Calculator

Estimate calories to gain weight safely. Set your goal rate and get daily surplus calories and weekly gain estimates.

mcg to IU Converter

Convert mcg to IU (and IU to mcg) for common vitamins. Choose vitamin type for accurate unit conversion.

Calorie Calculator

Calculate your daily calories (TDEE) with US goals like lose 1 lb/week or gain 0.5 lb/week. See weekly change and targets instantly.

Cholesterol Ratio Calculator

Free cholesterol ratio calculator. Enter total, HDL, LDL and triglycerides to get TC/HDL, LDL/HDL, TG/HDL, non-HDL and estimated LDL in seconds.

Face Shape Calculator

Free face shape calculator using forehead, cheekbones, jawline and face length to classify your face as oval, round, square, heart or diamond.