Cardivo guides

A1C chart: A1C to average blood sugar

Updated October 18, 2026 · Wellness education, not medical advice

Key takeaways

A1C reflects your average blood sugar over about 2–3 months.
Formula: eAG (mg/dL) = 28.7 × A1C − 46.7. An A1C of 7% ≈ 154 mg/dL.
Below 5.7% is normal, 5.7–6.4% prediabetes, 6.5% or higher diabetes.
A common goal for many adults with diabetes is below 7%, but targets are individual.

A1C to estimated average glucose (eAG)

A1C	Average glucose (mg/dL)	Average glucose (mmol/L)
5%	97 mg/dL	5.4 mmol/L
5.5%	111 mg/dL	6.2 mmol/L
5.7%	117 mg/dL	6.5 mmol/L
6%	126 mg/dL	7.0 mmol/L
6.5%	140 mg/dL	7.8 mmol/L
7%	154 mg/dL	8.6 mmol/L
7.5%	169 mg/dL	9.4 mmol/L
8%	183 mg/dL	10.2 mmol/L
8.5%	197 mg/dL	10.9 mmol/L
9%	212 mg/dL	11.7 mmol/L
10%	240 mg/dL	13.3 mmol/L
11%	269 mg/dL	14.9 mmol/L
12%	298 mg/dL	16.5 mmol/L

Calculated with the formula from the A1C-Derived Average Glucose (ADAG) study, eAG = 28.7 × A1C − 46.7, which the American Diabetes Association uses for its eAG calculator.

What the ranges mean

A1C	Category
Below 5.7%	Normal
5.7–6.4%	Prediabetes
6.5% or higher	Diabetes range (confirm with your doctor)

Common A1C goals

Below 7% for many nonpregnant adults with diabetes.
Lower (such as below 6.5%) may be reasonable if it can be reached safely without lows.
Higher (such as below 8%) may be safer for older adults or those with frequent hypoglycemia or other health conditions.

When A1C and your meter disagree

A1C is an average — it doesn't show highs and lows. Two people with an A1C of 7% can have very different days. Anemia, recent blood loss or transfusion, kidney disease, pregnancy, and some hemoglobin variants can also make A1C less reliable. CGM metrics like time in range fill in the picture.

How often to test

Commonly every 3 months if you're adjusting treatment or not at goal, and every 6 months when stable.

Log your A1C results and daily readings in Cardivo to see how the two line up over time, and share a PDF with your care team.

This guide is general wellness education based on the public sources below. It is not medical advice, diagnosis, or treatment. Cardivo is not a medical device. If you think you are having a medical emergency, call 911.

Frequently asked questions

What is a normal A1C?

Below 5.7% is normal. 5.7–6.4% is prediabetes and 6.5% or higher is in the diabetes range.

What average blood sugar is an A1C of 7?

An A1C of 7% corresponds to an estimated average glucose of about 154 mg/dL (8.6 mmol/L).

How do you convert A1C to average glucose?

Use the ADAG formula: estimated average glucose (mg/dL) = 28.7 × A1C − 46.7. Divide by 18 for mmol/L.

Sources

Cardivo is an ad-free iPhone app that reads heart rate and HRV from your fingertip on the camera in about 30 seconds — no Apple Watch needed — and keeps blood pressure, blood sugar, and mood in one journal you can share with your doctor as a PDF. Download on the App Store.