Medical Calculators

Accurate medical calculations at your fingertips

Fluid Deficit (4-2-1 rule)

Hourly maintenance fluid (mL/h) by 4-2-1 rule.

GFR (MDRD 4-variable)

Estimated GFR using MDRD 4-variable equation.

Heart Rate Max (Age-Predicted)

Estimated max HR: 220 - age (simple formula).

Ideal Body Weight (Female)

Estimated ideal body weight for adult females (Devine formula).

Ideal Body Weight (Male)

Estimated ideal body weight for adult males (Devine formula).

Lean Body Weight (James)

Estimated lean body weight (James formula).

Liquid Dose (mg to mL)

Convert dose in mg to volume (mL) using concentration.

Mean Arterial Pressure

MAP ≈ (2×DBP + SBP)/3.

Osmolarity (Serum)

Calculated serum osmolality: 2×Na + Glu/18 + BUN/2.8.

Target HR (Karvonen)

Target heart rate by % of HR reserve (Karvonen).

Weight-Based Drug Dose

Dose = dose_per_kg × weight (kg).

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