Anion Gap
Screens for high-anion-gap metabolic acidosis.
RESULT
Anion Gap
What is Anion Gap?
Screens for high-anion-gap metabolic acidosis. Anion Gap is intended for use in: Adults.
How to Use the Anion Gap Calculator
- Enter Sodium (Na) in mEq/L.
- Enter Chloride (Cl) in mEq/L.
- Enter Bicarbonate (HCO3) in mEq/L.
- Enter Potassium (K, optional) in mEq/L.
- Click Calculate to see your result and interpretation.
Formula & Version
This calculator uses formula version 1.0, last reviewed September 2026.
Clinical Considerations & Limitations
- Normal range shifts depending on whether potassium is included (≈8-12 mEq/L without K; ≈12-16 with K) and on the lab's albumin-adjusted reference range.
References
- Emmett M, Narins RG, Medicine 1977;56:38-54
Frequently Asked Questions
What is Anion Gap?
Screens for high-anion-gap metabolic acidosis.
Who is Anion Gap intended for?
Adults. Always confirm applicability to your specific patient before use.
What are the limitations of Anion Gap?
Normal range shifts depending on whether potassium is included (≈8-12 mEq/L without K; ≈12-16 with K) and on the lab's albumin-adjusted reference range.
What formula or reference does Anion Gap use?
Emmett M, Narins RG, Medicine 1977;56:38-54
Is Anion Gap a diagnosis?
No. Anion Gap produces a score or estimate to support clinical decision-making — it is not a diagnosis and should be interpreted alongside full clinical judgement.
Medical Disclaimer: Medical calculators are provided for informational and educational purposes only. Results should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always verify results with a qualified healthcare professional.
