How to use this tool
- Choose whether your result is in percent or mmol/mol.
- Type the HbA1c value from your report.
- Read the converted value, estimated average glucose and the diagnostic range.
Two units for the same test
US laboratories report HbA1c as a percentage (the NGSP/DCCT unit). The UK, Europe and many other countries use mmol/mol (the IFCC unit). Laboratories in India and Pakistan may report either, and often both. The master equation linking them is IFCC = 10.929 × (NGSP − 2.15).
HbA1c chart
| HbA1c % | mmol/mol | eAG mg/dL | eAG mmol/L |
|---|---|---|---|
| 5.0 | 31 | 97 | 5.4 |
| 5.7 | 39 | 117 | 6.5 |
| 6.5 | 48 | 140 | 7.8 |
| 7.0 | 53 | 154 | 8.6 |
| 8.0 | 64 | 183 | 10.2 |
| 9.0 | 75 | 212 | 11.8 |
| 10.0 | 86 | 240 | 13.4 |
Diagnostic ranges
The American Diabetes Association uses below 5.7% as normal, 5.7–6.4% as prediabetes and 6.5% or above as diabetes. The WHO and UK NICE use 48 mmol/mol (6.5%) for diabetes, and in the UK 42–47 mmol/mol (6.0–6.4%) is often called non-diabetic hyperglycaemia. A diagnosis normally needs a repeat test unless symptoms are clear. Anaemia, haemoglobin variants, pregnancy and recent blood loss can make HbA1c misleading.
Frequently asked questions
What is a normal HbA1c?
Below 5.7% (39 mmol/mol) under ADA criteria.
What does HbA1c 6.5 mean?
6.5% (48 mmol/mol) is the threshold for diagnosing diabetes, usually confirmed with a second test.
How do I convert HbA1c % to mmol/mol?
Subtract 2.15 and multiply by 10.929. 7% becomes 53 mmol/mol.
What average glucose is HbA1c 7?
About 154 mg/dL or 8.6 mmol/L.
Sources and references
- Nathan DM et al. Translating the A1C assay into estimated average glucose values. Diabetes Care 2008;31:1473–8
- American Diabetes Association: Standards of Care in Diabetes, Diagnosis and Classification
- IFCC/NGSP HbA1c conversion (NGSP)