HbA1c Converter: mmol/mol, % and Average Glucose

Type any one of the three. Get the other two, and the band it falls in.

HbA1c % (US)

Quick reference table

HbA1c	Average glucose (mg/dL)	Average glucose (mmol/L)	Category
5%	97	5.4	Normal range
5.7%	117	6.5	Prediabetes range
6%	125	7	Prediabetes range
6.5%	140	7.8	Diabetes range
7%	154	8.6	Diabetes range
8%	183	10.2	Diabetes range
9%	212	11.7	Diabetes range
10%	240	13.3	Diabetes range

Conversion uses the ADAG study formula adopted by the American Diabetes Association.

Hemoglobin A1c is reported two ways. The United States uses a percentage; the UK, Ireland, most of Europe, Australia and India use mmol/mol. They are the same measurement in different units: 42 mmol/mol is 6.0%, 48 mmol/mol is 6.5%, and 53 mmol/mol is 7.0%. Both convert to an average blood sugar over the last two to three months.

The common conversions

HbA1c in percent (US) and mmol/mol (UK and much of the world), with the average blood sugar each one reflects.

HbA1c %	mmol/mol	Avg glucose	Meaning
5.0	31	97 mg/dL · 5.4 mmol/L	Normal
5.5	37	111 mg/dL · 6.2 mmol/L	Normal
5.7	39	117 mg/dL · 6.5 mmol/L	Prediabetes begins
6.0	42	126 mg/dL · 7.0 mmol/L	Prediabetes
6.4	46	137 mg/dL · 7.6 mmol/L	Top of prediabetes
6.5	48	140 mg/dL · 7.8 mmol/L	Diabetes threshold
7.0	53	154 mg/dL · 8.6 mmol/L	Common treatment target
8.0	64	183 mg/dL · 10.2 mmol/L	Above target
9.0	75	212 mg/dL · 11.8 mmol/L	Well above target
10.0	86	240 mg/dL · 13.4 mmol/L	Needs prompt attention

Look up any value, 4.5 to 12.0 percent

HbA1c %	mmol/mol	Avg glucose mg/dL	Avg glucose mmol/L	Range
4.5	26	82	4.6	Normal
4.6	27	85	4.7	Normal
4.7	28	88	4.9	Normal
4.8	29	91	5.1	Normal
4.9	30	94	5.2	Normal
5.0	31	97	5.4	Normal
5.1	32	100	5.6	Normal
5.2	33	103	5.7	Normal
5.3	34	105	5.8	Normal
5.4	36	108	6.0	Normal
5.5	37	111	6.2	Normal
5.6	38	114	6.3	Normal
5.7	39	117	6.5	Prediabetes
5.8	40	120	6.7	Prediabetes
5.9	41	123	6.8	Prediabetes
6.0	42	125	6.9	Prediabetes
6.1	43	128	7.1	Prediabetes
6.2	44	131	7.3	Prediabetes
6.3	45	134	7.4	Prediabetes
6.4	46	137	7.6	Prediabetes
6.5	48	140	7.8	Diabetes range
6.6	49	143	7.9	Diabetes range
6.7	50	146	8.1	Diabetes range
6.8	51	148	8.2	Diabetes range
6.9	52	151	8.4	Diabetes range
7.0	53	154	8.6	Diabetes range
7.1	54	157	8.7	Diabetes range
7.2	55	160	8.9	Diabetes range
7.3	56	163	9.1	Diabetes range
7.4	57	166	9.2	Diabetes range
7.5	58	169	9.4	Diabetes range
7.6	60	171	9.5	Diabetes range
7.7	61	174	9.7	Diabetes range
7.8	62	177	9.8	Diabetes range
7.9	63	180	10.0	Diabetes range
8.0	64	183	10.2	Diabetes range
8.1	65	186	10.3	Diabetes range
8.2	66	189	10.5	Diabetes range
8.3	67	192	10.7	Diabetes range
8.4	68	194	10.8	Diabetes range
8.5	69	197	10.9	Diabetes range
8.6	70	200	11.1	Diabetes range
8.7	72	203	11.3	Diabetes range
8.8	73	206	11.4	Diabetes range
8.9	74	209	11.6	Diabetes range
9.0	75	212	11.8	Diabetes range
9.1	76	214	11.9	Diabetes range
9.2	77	217	12.1	Diabetes range
9.3	78	220	12.2	Diabetes range
9.4	79	223	12.4	Diabetes range
9.5	80	226	12.6	Diabetes range
9.6	81	229	12.7	Diabetes range
9.7	83	232	12.9	Diabetes range
9.8	84	235	13.1	Diabetes range
9.9	85	237	13.2	Diabetes range
10.0	86	240	13.3	Diabetes range
10.1	87	243	13.5	Diabetes range
10.2	88	246	13.7	Diabetes range
10.3	89	249	13.8	Diabetes range
10.4	90	252	14.0	Diabetes range
10.5	91	255	14.2	Diabetes range
10.6	92	258	14.3	Diabetes range
10.7	93	260	14.4	Diabetes range
10.8	95	263	14.6	Diabetes range
10.9	96	266	14.8	Diabetes range
11.0	97	269	14.9	Diabetes range
11.1	98	272	15.1	Diabetes range
11.2	99	275	15.3	Diabetes range
11.3	100	278	15.4	Diabetes range
11.4	101	280	15.6	Diabetes range
11.5	102	283	15.7	Diabetes range
11.6	103	286	15.9	Diabetes range
11.7	104	289	16.1	Diabetes range
11.8	105	292	16.2	Diabetes range
11.9	107	295	16.4	Diabetes range
12.0	108	298	16.6	Diabetes range

mmol/mol from the IFCC formula, average glucose from the ADAG study. Ranges use the American Diabetes Association thresholds: under 5.7 normal, 5.7 to 6.4 prediabetes, 6.5 and above diabetes.

Targets are personal: a fit 45 year old and a frail 85 year old are given different goals.

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Track your blood sugar Blood sugar questions, answered

Daily readingsA1c is the average. Readings show where the spikes are.A walkA walk after a meal moves the number more than most things you can buy.

Common questions

What does HbA1c actually measure?

HbA1c measures how much sugar has attached to the hemoglobin in your red blood cells, which is called glycated hemoglobin. Because red blood cells live about three months, the result reflects your average blood sugar over roughly the past three months. That makes it a bigger picture number than any single finger-prick reading.

What A1c level means prediabetes or diabetes?

An A1c from 5.7 to 6.4 percent falls in the prediabetes range, and 6.5 percent or higher on two tests is used to diagnose diabetes. Below 5.7 percent is considered normal. One result in the higher ranges does not settle it on its own, so confirm what your number means with your own doctor.

Why is my A1c different from my meter readings?

Your meter shows your blood sugar at one moment, while A1c averages every hour of the past three months, including nights and the hours after meals you never test. Conditions that affect red blood cells, such as anemia or kidney disease, can also push A1c up or down. If the two seem far apart, ask your doctor to help sort out which is telling the truer story.

How often should I have my A1c tested?

People with stable, well-controlled diabetes are usually tested twice a year. If your treatment has changed or your sugars are above target, every three months is common. People with prediabetes are often checked once a year, but your own doctor will set the right schedule for you.