Creatinine has two units, one is mg/dL and the other is umol/L. 1 mg/dL is equivalent to 88.4 umol/L. Creatinine is an indicator of kidney function and is often seen in clinical practice. A decrease in creatinine is not of great clinical significance, while an increase in creatinine represents an abnormality in kidney function and is of greater clinical significance. For the unit of this indicator, mg/dL was commonly used to calculate in the past, while umol/L is often applied at present, and the conversion relationship between these two has been mentioned above. These two units are only a matter of habit, there is no essential difference. mg/dL is often used when applying certain formulas to calculate the glomerular filtration rate, because those formulas appear at about the same time as mg/dL appears. But with this conversion formula, there is no obstacle to the process of these calculations.