Rex says
Same equations the textbooks use — just way less awkward. Pop in your stats and I'll tell you what the number actually means for you.
Try a scenario
Click to load — tweak from there.Inputs
Result
Corrected Na (1.6 factor)
136.0
Corrected Na (2.4 factor)
140.0
Free water deficit (L)
0.00
Total body water (L)
42.0
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter measured sodium (mEq/L).
- 2Enter serum glucose (mg/dL).
- 3Enter body weight (kg).
- 4Enter sex.
- 5Read your corrected na (1.6 factor) on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
High glucose pulls water intravascularly and dilutes measured sodium. This corrects for it using both the classic and Hillier factors, and estimates the free water deficit.
Worked example
Using the values the calculator loads with:
Inputs
- Measured sodium: 128 mEq/L
- Serum glucose: 600 mg/dL
- Body weight: 70 kg
- Sex: Male
Results
- Corrected Na (1.6 factor): 136
- Corrected Na (2.4 factor): 140
- Free water deficit (L): 0
- Total body water (L): 42
What each field means
Inputs
- Measured sodium (mEq/L)
- The measured sodium used in the calculation, measured in mEq/L. Starts at 128 mEq/L so you have a working example on load.
- Serum glucose (mg/dL)
- The serum glucose used in the calculation, measured in mg/dL. Starts at 600 mg/dL so you have a working example on load.
- Body weight (kg)
- The body weight used in the calculation, measured in kg. Starts at 70 kg so you have a working example on load.
- Sex
- Pick the option that matches your situation — the maths changes per option. Choices: Male, Female.
Results
- Corrected Na (1.6 factor)
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Corrected Na (2.4 factor)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Free water deficit (L)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total body water (L)
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Which correction factor is right?
The 2.4 Hillier factor fits better at glucose above 400 mg/dL; 1.6 is the traditional figure and closer at mild elevations.
How fast should sodium be corrected?
Slowly. Rapid correction of chronic hyponatremia risks osmotic demyelination — this is a clinical decision, not a calculator output.
Accuracy and limitations
- Population formulas describe averages; individual bodies vary, especially at the extremes of height, age, or muscle mass.
- Results do not account for medical conditions, medication, or pregnancy.
- Use this as a directional reference, not a diagnosis — talk to a clinician before acting on it.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Corrected Sodium Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/corrected-sodium
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/corrected-sodium" target="_blank" rel="noopener">Corrected Sodium Calculator — RevenueLab</a> (2026).</p>
Source: [Corrected Sodium Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/corrected-sodium) (2026).