Corrected Sodium Calculator

How it is calculated

The tool applies the Katz correction: corrected Na = Na + 1.6 × (glucose − 100) / 100. Sodium is in mEq/L (the same number as mmol/L) and glucose is in mg/dL. In plain terms, 1.6 mEq/L is added for every 100 mg/dL of glucose above 100. The engine does no unit conversion, so a glucose in mmol/L would give a wrong answer. If glucose is below 100 the term becomes negative and the corrected sodium is slightly lower than measured. The result is shown to one decimal with mEq/L. It is an estimate: some sources use a larger factor at very high glucose, which this tool does not.

Common mistakes

• Entering glucose in mmol/L (for example 33) instead of mg/dL (600). The tool expects mg/dL.
• Using the corrected value to ignore a real sodium problem. The correction only removes the dilution effect of glucose; other causes of low sodium remain.
• Applying the correction to a normal glucose and expecting a change; at 100 mg/dL the correction is exactly zero.
• Treating 1.6 as the only accepted factor. Some references use 2.4 per 100 mg/dL, and this tool uses the 1.6 version only.
• Entering the corrected sodium back into the sodium field, which corrects it twice.