GPAtlas🧮 Clinical calculator · Diabetes, lipids and hormones
HbA1c to estimated average glucose
Converts an HbA1c in International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) units, the mmol/mol used in the UK, to an estimated average glucose in mmol/L, so a result can be discussed against the numbers a person sees on their own meter.
Free to use, no account needed. Result: Estimated average glucose. Last reviewed 7 Oct 2026.
The calculator runs in your browser on this page. If it has not appeared, reload the page with JavaScript enabled.
Before you rely on the result: Estimated average glucose explains an HbA1c; it is not a measured glucose, and the conversion is internationally published, not NICE. HbA1c misleads with disturbed red cell turnover or an abnormal haemoglobin, and is less reliable in pregnancy.
Related Ocean Article: Type 2 Diabetes & Insulin therapy (T2DM).
Further reading: Prediabetes · Type 1 Diabetes & Insulin therapy (T1DM).
Part of the GPAtlas clinical calculators, each result explained, built by practising UK GPs.