Blood sugar logging guides

Fasting and after-meal blood sugar ranges, when to check, how to keep a log, and mg/dL ↔ mmol/L conversion — the things people look up most when tracking blood sugar.

• Normal fasting blood sugar and how to check itNormal fasting blood sugar (under 100 mg/dL), prediabetes (100–125), the diabetes threshold (126 or higher), and how to get an accurate fasting reading.
• Blood sugar after eating: ranges and timingAfter-meal blood sugar ranges (140, 180, 200 mg/dL), the difference between 1-hour and 2-hour checks, and when to start counting the time.
• When to check your blood sugarWhen should you check your blood sugar? What fasting, before-meal, 1- and 2-hour after-meal, and bedtime readings each tell you, plus logging tips.
• How to keep a blood sugar log (with example)What to include in a blood sugar log — date, time, time point, reading, meal, and notes — with an example log sheet and tips for sticking with it.
• Tracking blood sugar with an appWhat to look for in a blood sugar tracking app, why logging on your phone helps, and how to log blood sugar, weight, and meals together with Gly Log.
• Sharing your blood sugar log at a doctor visitHow to organize your home blood sugar readings for an appointment, what your care team finds easiest to read, and how to make a PDF report.
• Blood sugar unit conversion: mg/dL ↔ mmol/LHow to convert blood sugar between mg/dL and mmol/L (divide or multiply by 18), plus a chart of commonly used values.
• Using before- and after-meal readings to find meals that suit youPair a before-meal and after-meal reading for the same meal to see which foods raise your blood sugar the most. Here is how to log it.
• Keeping a gestational diabetes blood sugar logCommon blood sugar targets for gestational diabetes, the usual daily check times, and how to keep your log. Your care team's targets come first.
• Why it helps to track weight alongside blood sugarWhen is the most consistent time to weigh yourself? How to weigh under the same conditions and view your weight trend alongside your blood sugar.

This article is general health information and does not replace diagnosis or treatment. Targets and how often to check differ from person to person, so follow your care team first. If you have symptoms of low blood sugar or readings far outside your range, contact your care team right away.