ECW/TBW ratio
The share of your body water sitting outside the cells: extracellular water divided by total body water.
The share of your body water sitting outside the cells: extracellular water divided by total body water.
It is the one water number comparable between people, because dividing one compartment by the other cancels out body size.
Roughly 0.360 to 0.390 is the usual band, drifting up gently with age. A value above it points toward fluid retention or inflammation rather than toward a larger body.
Worth discussing a value that stays above the range on repeat measurements.
On a report in another language.
A lab report names this analyte in its own language. Vitals Vault recognises each of these and files them all under ECW/TBW ratio.
Catalog entry last updated 2026-08-29. Browse all 165 metrics.