Once upon a time I had 628mg/dl. At the time they told me it was unreadable high, but when I got it down (98 this last June!) they showed me my last four levels over the past two years and I was able to read it myself. When I asked why they told me it was unreadable at the time, when they obviously were able to have a precise number they told me that they usually avoided disclosing levels over 400 to avoid hurting peoples feelings. Right now I don't know if being told I had four times the healthy level would have motivated me or destroyed my resolve. Whatever. It's behind me and I intend to keep it that way.