Anion Gap Calculator
Calculate anion gap with albumin correction for medical diagnosis of electrolyte imbalances and acid-base disorders with clinical interpretations
Medical Disclaimer: This tool is for educational purposes only. Always consult qualified healthcare professionals for patient care decisions.
Clinical Scenarios
Laboratory Values
Required Values
mEq/L
Normal: 135-145 mEq/L
mEq/L
Normal: 95-105 mEq/L
mEq/L
Normal: 22-28 mEq/L
g/dL
Normal: 3.5-5.0 g/dL
Optional Values
mOsm/kg
mOsm/kg
Understanding Anion Gap
What is Anion Gap?
The difference between measured cations and anions in serum, used to evaluate acid-base disorders.
Calculation:
AG = Na+ - (Cl- + HCO3-). Normal range is typically 8-16 mEq/L.
Albumin Correction:
Add 2.5 mEq/L for each 1 g/dL decrease in albumin below 4.0 g/dL.
Clinical Significance:
High AG suggests metabolic acidosis with unmeasured anions (organic acids, toxins).
Clinical Applications
High Anion Gap Causes:
MUDPILES - Methanol, Uremia, Diabetic ketoacidosis, Propylene glycol, Iron/Isoniazid, Lactic acidosis, Ethylene glycol, Salicylates.
Normal Gap Acidosis:
Diarrhea, ureterosigmoidostomy, carbonic anhydrase inhibitors, hyperalimentation.
Low Anion Gap:
Usually due to laboratory error, hypoalbuminemia, or paraproteinemia (multiple myeloma).
Clinical Correlation:
Always interpret with arterial blood gas, clinical history, and physical examination.