Delta Ratio Calculator

About this calculator

The delta ratio (sometimes called delta-delta or ΔAG/ΔHCO3) helps clinicians tell whether a patient’s metabolic acidosis is a pure high-anion-gap process or a mixed disorder: it compares how far the anion gap has risen above normal to how far the bicarbonate has fallen below normal, using Delta ratio = (AG − 12) / (24 − HCO3) with 12 and 24 as the typical normal reference values (adjustable when local lab norms differ).

A ratio near 1 to 2 suggests a straightforward high-anion-gap metabolic acidosis (such as diabetic ketoacidosis), a ratio below 1 points toward a concurrent normal-anion-gap (hyperchloremic) acidosis, and a ratio above 2 suggests a coexisting metabolic alkalosis or a pre-existing elevated bicarbonate, since the bicarbonate has not fallen as much as the rising anion gap would predict. Physicians and intensive-care clinicians use it alongside arterial blood gas and electrolyte panels to unravel mixed acid-base disorders; enter the anion gap and bicarbonate, adjusting the normal values if your lab uses different reference ranges. Not medical advice.