Use this page for measured creatinine clearance with collection-time adjustment, BSA normalization, and adequacy checks to catch incomplete collections.
Why measured 24-hour CrCl still matters
Estimated equations are convenient, but a timed urine collection can add context in selected cases. The key is collection quality: inaccurate timing or missed urine can invalidate results even when math is correct.
Collection adequacy is a core feature, not a bonus
This calculator estimates creatinine excretion per kg/day and compares it with expected sex-specific ranges. If values fall outside expected bands, results should be interpreted cautiously and repeat collection may be needed.
How to interpret outputs
Raw CrCl (mL/min): direct measured clearance.
BSA-corrected CrCl: normalized to 1.73 m² for staging context.
CKD stage gauge: quick placement on G1 to G5 spectrum.
Adequacy bar: visual check for under/over-collection risk.
FAQ
What if the collection was incomplete?
Clearance will be wrong—incomplete collections are a common error.
Do units need to match exactly?
Follow the formula’s units or convert carefully—errors are dangerous.
Should I compare to eGFR?
They measure different things—your clinician interprets labs in context.
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