Labs · Whole blood
Hemoglobin A1c (HbA1c)
Glycated hemoglobin · adult diagnosis, monitoring and test limitations
Reference range
- <5.7%
- Below the prediabetes range in nonpregnant individuals4
- 5.7–6.4%
- Prediabetes range in nonpregnant individuals4
- ≥6.5%
- Nonpregnant diagnostic threshold; confirmation required unless hyperglycemia is unequivocal1
- <7%
- Goal for many nonpregnant adults without severe hypoglycemia or hypoglycemia affecting health or quality of life; individualized2
Interpretation
A1c reflects average glucose over approximately three months. Estimated average glucose (eAG) translates the percentage into glucose units; it is not the same as a current meter reading.4
Watch for
- A1c is not a substitute for assessment of acute glucose changes or hypoglycemia. A reassuring average can conceal important short-term variation.4
Excerpt. The full entry also covers diagnostic confirmation, common causes, and nursing actions.
Citations
- ADA Standards of Care 2026 — Diagnosis and ClassificationAmerican Diabetes Association · clinical facts paraphrased
- ADA Standards of Care 2026 — Glycemic GoalsAmerican Diabetes Association · clinical facts paraphrased
- NGSP — Factors that Interfere with HbA1c Test ResultsNational Glycohemoglobin Standardization Program · clinical facts paraphrased
- NIDDK — The A1C Test & DiabetesNational Institute of Diabetes and Digestive and Kidney Diseases · public domain
Last source-fidelity review: Sep 20, 2026
Reference only · Always follow your facility’s policies and verify with your provider.
