Serum Osmolality
Calculate osmolality and osmolal gap.
Lab Values
mEq/L
Serum sodium
mg/dL
Serum glucose
mg/dL
Blood urea nitrogen
mOsm/kg
From lab (for gap calculation)
Calculated Osmolality
0 mOsm/kg
Osmolal Gap: 0 mOsm/kg
Normal Gap
Calculated
0 mOsm/kg
Measured
295 mOsm/kg
Gap
0 mOsm/kg
Normal Gap
<10
Formula
Osm = (2 × Na) + (Glucose/18) + (BUN/2.8)
= (2 × 140) + (100/18) + (20/2.8) = 0 mOsm/kg
Frequently Asked Questions
How to Use
About the Osmolality Calculator
What it calculates
This osmolality calculator applies a validated clinical scoring method used in healthcare settings. Serum osmolality calculation.
When to use it
Use as a clinical decision support aid alongside professional judgment — not as a standalone diagnosis.
Example
Adjust the inputs above to model your specific scenario with the Osmolality Calculator.
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