Is my blood sugar data private?

Yes. All readings, medications and settings are stored only in your browser using local storage. Nothing is uploaded to any server, so your health data never leaves your device.

How is the estimated A1C calculated?

It uses the standard ADAG formula: A1C% = (average glucose in mg/dL + 46.7) / 28.7, applied to your readings over roughly the last 90 days. It is an estimate and not a replacement for a lab A1C test.

Can I switch between mg/dL and mmol/L?

Yes. You can choose mg/dL or mmol/L at any time. The conversion uses mmol/L = mg/dL / 18.0182, and the whole app updates to your preferred unit.

Can I export a report for my doctor?

Yes. You can export a PDF report, a CSV spreadsheet, or a full JSON backup. The PDF includes your averages, time-in-range, estimated A1C and a table of recent readings.

Is this tool medical advice?

No. This tool is for informational and tracking purposes only. Always consult your healthcare provider for diabetes management decisions.

🩸 Blood Sugar Tracker

Glucose, carbs, insulin & A1C — all on your device

This tool is for informational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider for diabetes management decisions.

🔒 Private: all data is stored only in your browser (local storage). Nothing is uploaded.

Last Reading

mg/dL

7-Day Average

mg/dL

--%

Time in Range (7d)

70-180 mg/dL

Estimated A1C

% (≈90d)

Log Reading

Blood Glucose

mg/dL

mmol/L

Enter a value between 20 and 600 mg/dL

Reading Context

Date

Time

Notes (optional)

Log Carbs

Log Insulin

Trends

Today

Week

Month

3 Months

Low

In Range

High

Insights

Reading History

📊

No readings yet. Start tracking your blood sugar!

A1C / eAG Reference & Converter

Estimated average glucose (eAG) maps to A1C using the ADAG study: eAG (mg/dL) = 28.7 × A1C − 46.7.

A1C %	eAG mg/dL	eAG mmol/L

Convert A1C → eAG

Enter an A1C to see estimated average glucose.

Convert mg/dL ⇄ mmol/L

⇄

mmol/L = mg/dL ÷ 18.0182

About this tracker

Log every blood glucose reading with the time of day and a context tag (fasting, before/after meal, bedtime, random, or exercise), and optionally record carbohydrates and insulin. The dashboard shows your last reading, 7-day average, time-in-range and an estimated A1C. Switch freely between mg/dL and mmol/L — every value updates instantly. Set your personal target range and medications in Settings, and export a clean PDF, CSV or JSON backup to share with your doctor or move to another device. Everything stays in your browser; nothing is sent anywhere.