Anion Gap Calculator
Calculate the serum anion gap and delta-delta ratio for metabolic acidosis workup and acid-base disorder classification.
Medical Disclaimer
This calculator is for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making decisions about your health. Never disregard professional medical advice or delay seeking it because of results from this tool.
Inputs
Normal Na⁺: 136–145 mEq/L; hyponatremia: <136; hypernatremia: >145 mEq/L
Normal Cl⁻: 98–106 mEq/L; hyperchloremia >106 mEq/L may indicate normal-AG acidosis
Normal HCO₃⁻: 22–29 mEq/L; metabolic acidosis: <22; metabolic alkalosis: >29 mEq/L
Normal albumin: 3.5–5.0 g/dL; corrected AG = measured AG + 2.5 × (4.0 − albumin)
Results
Anion Gap
12mEq/L
Corrected AG (Albumin)
12mEq/L
How to Use This Calculator
- Enter serum sodium (Na⁺), chloride (Cl⁻), and bicarbonate (HCO₃⁻) in mEq/L.
- Set albumin level (g/dL) for albumin-corrected anion gap calculation.
- Review Anion Gap and corrected anion gap — normal is 8–12 mEq/L (or 3–11 with albumin correction).
- Elevated AG > 12 triggers MUDPILES differential (methanol, uremia, DKA, etc.).
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