I've come across users who get a reading in mmol/L and have no idea what it means because they are only familiar with mg/dL readings. Well hopefully the following will no longer cause any confusion.

10mg/dL - 0.5mmol/L
15mg/dL - 0.8mmol/L
20mg/dL - 1.1mmol/L
25mg/dL - 1.3mmol/L
30mg/dL - 1.6mmol/L
35mg/dL - 1.9mmol/L
40mg/dL - 2.2mmol/L
45mg/dL - 2.5mmol/L
50mg/dL - 2.7mmol/L
55mg/dL - 3.0mmol/L
60mg/dL - 3.3mmol/L
65mg/dL - 3.6mmol/L
70mg/dL - 3.8mmol/L
75mg/dL - 4.1mmol/L
80mg/dL - 4.4mmol/L
85mg/dL - 4.7mmol/L
90mg/dL - 5.0mmol/L
95mg/dL - 5.2mmol/L
100mg/dL - 5.5mmol/L
105mg/dL - 5.8mmol/L
110mg/dL - 6.1mmol/L
115mg/dL - 6.3mmol/L
120mg/dL - 6.6mmol/L
125mg/dL - 6.9mmol/L
130mg/dL - 7.2mmol/L
135mg/dL - 7.5mmol/L
140mg/dL - 7.7mmol/L

-Gear