A1C Estimated Average Glucose Calculator

Calculator Input

The page uses a centered single-column flow, while the input controls switch to 3 columns on large screens, 2 on smaller screens, and 1 on mobile.

Conversion mode

A1C (%)

Estimated average glucose (mg/dL)

Estimated average glucose (mmol/L)

Target eAG (mg/dL)

Decimal precision

Reading label

Test date

Reset

Plotly Graph

The line shows the A1C-to-eAG relationship. When you calculate a result, the chart highlights your point.

Example Data Table

A1C (%)	Estimated Average Glucose (mg/dL)	Estimated Average Glucose (mmol/L)
5.0	96.8	5.4
5.7	116.9	6.5
6.0	125.5	7.0
6.5	139.9	7.8
7.0	154.2	8.6
8.0	182.9	10.2
9.0	211.6	11.7

This example table helps users compare common A1C values against estimated daily average glucose in both major units.

Formula Used

Forward conversion: eAG (mg/dL) = 28.7 × A1C − 46.7

Unit conversion: eAG (mmol/L) = eAG (mg/dL) ÷ 18.0182

Reverse conversion: A1C = (eAG + 46.7) ÷ 28.7

A1C reflects average glycation over time, while estimated average glucose turns that lab value into a unit many people find easier to read and compare with day-to-day glucose records.

How to Use This Calculator

Select the direction of conversion.
Enter A1C, mg/dL, or mmol/L based on the chosen mode.
Add an optional target eAG value for comparison.
Choose your preferred decimal precision.
Optionally add a reading label and test date.
Press Calculate to show the result above the form.
Review the summary, graph, and example table.
Use the CSV or PDF buttons to download your result.

FAQs

1) What does estimated average glucose mean?

Estimated average glucose translates an A1C percentage into an average glucose value. It helps compare laboratory A1C results with everyday glucose readings shown in mg/dL or mmol/L.

2) Is eAG the same as a meter average?

Not exactly. eAG is derived from the A1C relationship, while a meter average depends on when and how often readings were collected. Missing highs or lows can make the two numbers differ.

3) Can this calculator convert both ways?

Yes. It converts A1C to estimated average glucose and also estimates A1C from glucose values entered in mg/dL or mmol/L.

4) Why are mg/dL and mmol/L both shown?

Different regions use different glucose units. Showing both makes the result easier to compare with lab reports, glucose meters, apps, and professional discussions.

5) Why might my daily readings not match the calculator result?

Sampling gaps, timing bias, illness, medication changes, and data coverage can all affect meter or sensor averages. A1C-based estimates summarize longer-term patterns, not single-day behavior.

6) Does the target comparison change the calculation?

No. The target field only shows how far your estimated average glucose sits above or below a reference value you choose.

7) Can I save the result for later?

Yes. Use the CSV button for spreadsheet-friendly data or the PDF button for a cleaner shareable summary.

8) Is this tool enough for diagnosis or treatment decisions?

No. This calculator is educational. Use it to organize information, then discuss interpretation and care decisions with a qualified clinician.

Result Export Preview

Label	Date	A1C (%)	eAG (mg/dL)	eAG (mmol/L)	Mode
Quarterly review	2026-03-21	7.0	154.2	8.6	a1c_to_eag