A1C Chart: Complete Reference Table & Guide

Q: What does an A1C of 6.5% mean in blood sugar?

An A1C of 6.5% corresponds to an eAG of approximately 140 mg/dL (7.8 mmol/L). This is the threshold used by the ADA to diagnose diabetes — meaning average blood sugar over the past 2–3 months has been around 140 mg/dL.

Q: What is A1C 7% in mg/dL?

An A1C of 7.0% equals an eAG of approximately 154 mg/dL (8.6 mmol/L). This is the ADA's recommended target for most adults managing diabetes.

Q: How accurate is the A1C to eAG conversion?

The ADA ADAG formula has a correlation of 0.92 between A1C and eAG. Individual variation means your personal A1C may correspond to a somewhat different average glucose than the chart shows.

Q: What A1C corresponds to a blood sugar of 200 mg/dL?

An average blood sugar of 200 mg/dL corresponds to an estimated A1C of approximately 8.6%: A1C = (200 + 46.7) ÷ 28.7 = 8.59%.

Q: Is an A1C of 5.7% prediabetes?

Yes — an A1C of exactly 5.7% is at the lower boundary of the prediabetes range (5.7%–6.4%). Many people at this level successfully bring A1C back into the normal range through lifestyle changes.

Q: How do I convert A1C to mmol/L?

First calculate eAG in mg/dL using (28.7 × A1C%) − 46.7, then divide by 18.016 to convert to mmol/L. For example: A1C 7.5% → 168.6 mg/dL → 9.4 mmol/L.

Quick reference

A1C below 5.7% = Normal · 5.7–6.4% = Prediabetes · 6.5%+ = Diabetes. An A1C of 7.0% equals an estimated average glucose (eAG) of 154 mg/dL (8.6 mmol/L) — the ADA target for most adults with diabetes. Use this chart to look up your A1C and find the corresponding blood glucose equivalent.

📋 7 min read🔬 ADA formula📅 Updated April 2026

A1C to eAG Complete Reference Chart

This table shows every 0.5% A1C increment from 5.0% to 14.0%, with corresponding eAG in both mg/dL and mmol/L, calculated using the ADA ADAG formula.

A1C %	eAG (mg/dL)	eAG (mmol/L)	Range
5.0%	97	5.4	Normal
5.5%	111	6.2	Normal
5.7%	117	6.5	Upper Normal
6.0%	126	7.0	Prediabetes
6.4%	137	7.6	Prediabetes (upper)
6.5%	140	7.8	Diabetes threshold
7.0%	154	8.6	ADA target (most adults)
7.5%	169	9.4	Above target
8.0%	183	10.2	Above target
8.5%	197	10.9	High
9.0%	212	11.8	High
9.5%	226	12.6	High
10.0%	240	13.4	Very high
11.0%	269	14.9	Very high
12.0%	298	16.5	Very high
13.0%	326	18.1	Severely high
14.0%	355	19.7	Severely high

Formula: eAG (mg/dL) = (28.7 × A1C%) − 46.7 · Source: ADA ADAG study · NIDDK

How to Read This A1C Chart

Each row shows an A1C percentage and the corresponding estimated average glucose (eAG) — the equivalent blood sugar value in units you'd see on a home glucose meter. The Range column shows the clinical classification:

Normal: A1C below 5.7% — blood sugar has been consistently healthy
Prediabetes: A1C 5.7%–6.4% — elevated but not yet at the diabetes threshold; often reversible
Diabetes: A1C 6.5% or higher — used to diagnose diabetes (requires confirmation on a second test)

For an interactive visual version of this chart, see our HbA1c Chart tool — it lets you look up any A1C value and highlights where it falls on the spectrum.

The Formula Behind the Chart

Every value in this chart is calculated using the ADA ADAG (A1C-Derived Average Glucose) formula, established in a landmark study that collected over 2,700 glucose readings per participant across 3 months:

        eAG (mg/dL) = (28.7 × A1C%) − 46.7
        eAG (mmol/L) = eAG (mg/dL) ÷ 18.016 · Reverse: A1C% = (eAG + 46.7) ÷ 28.7
      

To calculate any specific A1C value not shown in the chart, use our A1C Calculator for instant conversion with interpretation.

A1C Targets by Situation

The chart shows the same thresholds for everyone, but clinical A1C targets vary based on individual circumstances:

Situation	A1C Target	eAG Target
No diabetes (general population)	< 5.7%	< 117 mg/dL
Most adults with diabetes	< 7.0%	< 154 mg/dL
Lower risk, longer life expectancy	< 6.5%	< 140 mg/dL
Elderly / high hypoglycemia risk	< 8.0%	< 183 mg/dL
Pregnancy (pre-existing diabetes)	< 6.0–6.5%	< 126–140 mg/dL
Children/teens with type 1	< 7.5%	< 169 mg/dL

How to Track A1C Changes Over Time

A1C reflects a 2–3 month rolling average, so meaningful changes take time to appear. Here's how to interpret movement in the chart:

A drop of 0.5% (e.g., 8.0% → 7.5%) reduces average glucose by about 14 mg/dL — a meaningful, measurable improvement
A drop of 1.0% (e.g., 8.0% → 7.0%) reduces average glucose by about 29 mg/dL — typically achievable with sustained lifestyle changes or medication
Changes below 0.3% may fall within the margin of error for A1C testing — two tests within 0.3% of each other are essentially the same result

If your A1C has changed between tests, use the chart to see how the corresponding eAG has shifted — sometimes seeing the mg/dL change makes the improvement feel more concrete.

Frequently Asked Questions

What does an A1C of 6.5% mean in blood sugar?

An A1C of 6.5% corresponds to an eAG of approximately 140 mg/dL (7.8 mmol/L). This is the threshold used by the ADA and WHO to diagnose diabetes — meaning average blood sugar over the past 2–3 months has been around 140 mg/dL. Note that this is a 3-month average — individual readings will be higher after meals and lower when fasting.

What is A1C 7% in mg/dL?

An A1C of 7.0% equals an eAG of approximately 154 mg/dL (8.6 mmol/L). This is the ADA's recommended target for most adults managing diabetes. It represents an average blood glucose of 154 mg/dL across all times of day — fasting, post-meal, overnight — over the past 2–3 months.

How accurate is the A1C to eAG conversion?

The ADA ADAG formula has a correlation of 0.92 between A1C and eAG across the study population. However, individual variation means your personal A1C may correspond to a somewhat different average glucose than the chart shows. People with certain hemoglobin variants, anemia, or kidney disease may have A1C values that don't accurately reflect their average glucose. The chart provides a population-level estimate, not an individualized measurement.

What A1C corresponds to a blood sugar of 200 mg/dL?

An average blood sugar of 200 mg/dL (11.1 mmol/L) corresponds to an estimated A1C of approximately 8.6%: A1C = (200 + 46.7) ÷ 28.7 = 8.59%. This is significantly above the ADA's target of 7.0% for most adults with diabetes. Use our Glucose to A1C Calculator to convert any average glucose to an estimated A1C.

Is an A1C of 5.7% prediabetes?

Yes — an A1C of exactly 5.7% is at the lower boundary of the prediabetes range (5.7%–6.4%). At this level, average blood sugar is slightly higher than normal, but not yet at the diabetes diagnostic threshold. Many people at 5.7% successfully bring their A1C back into the normal range (below 5.7%) through dietary improvements and increased physical activity. It's worth discussing with your doctor.

How do I convert A1C to mmol/L?

To convert A1C to eAG in mmol/L, use this two-step process: first calculate eAG in mg/dL using the formula (28.7 × A1C%) − 46.7, then divide by 18.016 to convert to mmol/L. For example: A1C 7.5% → eAG = (28.7 × 7.5) − 46.7 = 168.6 mg/dL → 168.6 ÷ 18.016 = 9.4 mmol/L. Or use our A1C Calculator which shows both units simultaneously.