My blood sugar journal

Everything on this page lives only in your browser on this device. Nothing is uploaded — your readings never leave your phone or computer.

Good to know: Safari on iPhone/iPad deletes site storage after about 7 days without a visit — your journal can disappear with it. Two safety nets: Export your data now and then, and Print a sheet before doctor visits.

Add a reading

Your trend

Shape = when measured: ● fasting ◆ after eating ○ other    Color = classification: ● low● normal● elevated● high

Entries

    Reference ranges (ADA): fasting normal 70–99 mg/dl · after meals normal below 140 mg/dl. The printed sheet includes date, time, context and note for every entry.

    Where is this data stored?

    Your readings never leave this device. They are saved only in this browser's local storage — nothing is sent to our servers, nothing is tied to an account, and we could not look at your numbers even if we wanted to.

    That privacy has practical consequences worth knowing:

    • One journal per device and browser. Readings saved on your phone do not appear on your laptop. The JSON export/import above is the bridge.
    • Clearing browser data deletes the journal — permanently, and we cannot restore it.
    • Safari on iPhone/iPad deletes local data after about 7 days without a visit. Adding this page to your home screen prevents that.
    • Private/incognito windows do not keep anything after closing.

    The safety nets: export a JSON backup now and then, and print the doctor's sheet before appointments — paper and PDF are the copies that count for your medical record.