Anion Gap
Compute the anion gap (Na - (Cl + HCO3)) and the albumin-corrected anion gap (+2.5 mEq/L per 1 g/dL drop below 4.0).
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Sodium
- 140 mEq/L
- Chloride
- 100 mEq/L
- Bicarbonate
- 24 mEq/L
- Albumin
- 4 g/dL
Result: AG 16; corrected AG 16
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Sodium
- Chloride
- Bicarbonate
- Albumin (optional; omit for the uncorrected gap)
What this is
Sophie Well returns both values so a low albumin doesn't mask a real high-anion-gap metabolic acidosis. Source: Emmett & Narins, Medicine 1977; Figge et al., Crit Care Med 1998.
When to use it
Use this on any chemistry panel that shows acidosis, when MUDPILES is on the differential, or when albumin is significantly low and the uncorrected gap looks deceptively normal. The Anion Gap & Delta-Delta tool extends this with the delta-gap / delta-bicarb ratio for mixed disorders.
How this is calculated
Emmett M, Narins RG. Clinical use of the anion gap. Medicine (Baltimore). 1977;56(1):38-54. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.
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