How this calculator works
Use protein and creatinine concentrations from the same urine specimen. The ratio partly accounts for urine dilution. The mg/mmol conversion uses creatinine molecular mass 113.12 g/mol. Total protein includes albumin and other proteins. This page does not turn the spot ratio into an exact daily protein loss or apply a universal reference interval. The result is an estimate for information only and is not medical advice.
Formula
Ratio in mg/g = solute in mg/L / creatinine in g/L. Ratio in mg/mmol = ratio in mg/g × 0.11312. Rearrange to recover a missing concentration. Creatinine mass and molar units are converted before taking the ratio.
Worked example
Urine protein 3 mg/dL and creatinine 100 mg/dL give 30 mg/g, or 3.3936 mg/mmol. Values 30 and 100 mg/dL give 300 mg/g, or 33.936 mg/mmol.
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Frequently asked questions
Can I mix mg/L and mg/dL?
Yes, when you select the matching unit beside each input. The calculator converts both to consistent concentrations.
Is a zero result possible?
Yes, zero measured solute with positive creatinine gives zero. A zero ratio cannot uniquely recover creatinine.
Is this a 24-hour collection?
No. This is a spot specimen ratio. A timed collection measures excretion over an interval and is a different calculation.