Urine Specific Gravity
Specific gravity measures how concentrated your urine is by comparing its density to that of pure water. It reflects the balance of water and dissolved substances your kidneys are handling.
This number is a practical gauge of your hydration and of how well your kidneys concentrate or dilute urine. It rises when you're dehydrated and falls when you're well hydrated or drinking large amounts. Because the kidneys fine-tune this balance constantly, specific gravity offers insight into both your fluid status and kidney function.
A higher specific gravity often means concentrated urine from not drinking enough, sweating heavily, or fluid loss. Persistently high values can sometimes reflect substances like glucose or protein in the urine, which a clinician may explore further.
A lower specific gravity generally reflects dilute urine from good hydration or a large fluid intake. Consistently low values that don't fit your fluid intake can occasionally point to how the kidneys are concentrating urine and may warrant a clinician's review.
Values commonly fall between about 1.005 and 1.030, shifting with your hydration through the day. Your clinician interprets specific gravity alongside your fluid intake and the rest of your results rather than in isolation.
Sources
Educational context only, not medical advice or a diagnosis. Reference ranges vary by lab, age and sex; always discuss your results with a clinician.