Anion Gap Calculator.
Quick and easy to use anion gap calculator Enter required data to get the result:
Sodium: mmol/L or mEq/L
Chloride: mmol/L or mEq/L
Bicarbonate: mmol/L or mEq/L
Potassium (optional): mmol/L or mEq/L
No fuss calculator. It does what it says on the tin.