Medical Biostatistics Calculators

Free interactive calculators for essential biostatistics concepts. Perfect for medical students preparing for USMLE, MCCQE, UKMLA, and AMC exams.

Available Calculators

  • NNT/NNH Calculator — Calculate Number Needed to Treat and Number Needed to Harm from control and experimental event rates. Also computes Absolute Risk Reduction and Relative Risk Reduction.
  • Relative Risk & Odds Ratio Calculator — Compute RR and OR from a 2×2 table with confidence intervals.
  • Confidence Interval Calculator — Calculate confidence intervals for proportions and means at various confidence levels.
  • Power & Sample Size Calculator — Determine statistical power or required sample size for clinical studies.

How to Use

Enter your values into the calculator fields and get instant results with step-by-step explanations. Each calculator includes the formulas used and interpretation guidance for exam preparation.

2×2 Table Tool | Practice Questions | View Pricing