Normal levels range between 3.6 and 5.8 mM (mmol/l). In humans normal blood glucose levels are around 90 mg/dl, equivalent to 5mM (mmol/l). Since the molecular weight of glucose, C6H12O6, is about 180 g/mol, when calculated the total amount of glucose normally in circulating human blood is around 3.3 to 7g (assuming an ordinary adult blood volume of 5 litres). Blood glucose is measured in terms of molarity, measured in mmol/L or millimoles per litre. In the United States, and to a lesser extent elsewhere, mass concentration, measured in mg/dL.If a mg/dL figure is to be converted to mmol/L, it is to be divided by 18 or multiply by 0.055. Similarly to convert a mmol/L figure to mg/dL it is to be multiplied by 18 or divided by 0.055.