How do you convert HbA1c from % to mmol/mol?

Subtract 2.15 from the percentage and multiply by 10.929. For example, 5.6% is about 38 mmol/mol. To go the other way, divide mmol/mol by 10.929 and add 2.15.

What HbA1c is 48 mmol/mol in old units?

48 mmol/mol is about 6.5% in the old DCCT units. The UK switched from % to mmol/mol as the standard reporting unit in 2011.

What is estimated average glucose (eAG)?

eAG turns an HbA1c into an average glucose figure over the previous two to three months, using the ADAG study equation. It is an estimate for context, not a replacement for day-to-day glucose readings.

Does this tell me if I have diabetes?

No. This converter only changes the unit and estimates an average; it is not a diagnosis. HbA1c thresholds are for a clinician to apply alongside the rest of your picture.

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HbA1c Converter

UK labs report HbA1c in mmol/mol (IFCC); older and US results use % (DCCT). Convert between them instantly and see the estimated average glucose, no account needed.

HbA1c in %

IFCC mmol/mol = (DCCT% − 2.15) × 10.929. Estimated average glucose uses the ADAG study equation (Nathan et al., 2008).

How this is worked out

Uses the IFCC-NGSP master equation: mmol/mol = (DCCT% − 2.15) × 10.929. Estimated average glucose uses the ADAG study equation (Nathan et al., Diabetes Care 2008): eAG (mmol/L) = 1.59 × HbA1c% − 2.59.

This tool is for general wellbeing information and is not a diagnosis or medical advice. It places the numbers you enter in context; it cannot tell you whether you have a condition. If a result concerns you, or you have symptoms, speak to your GP.

Questions

How do you convert HbA1c from % to mmol/mol?: Subtract 2.15 from the percentage and multiply by 10.929. For example, 5.6% is about 38 mmol/mol. To go the other way, divide mmol/mol by 10.929 and add 2.15.
What HbA1c is 48 mmol/mol in old units?: 48 mmol/mol is about 6.5% in the old DCCT units. The UK switched from % to mmol/mol as the standard reporting unit in 2011.
What is estimated average glucose (eAG)?: eAG turns an HbA1c into an average glucose figure over the previous two to three months, using the ADAG study equation. It is an estimate for context, not a replacement for day-to-day glucose readings.
Does this tell me if I have diabetes?: No. This converter only changes the unit and estimates an average; it is not a diagnosis. HbA1c thresholds are for a clinician to apply alongside the rest of your picture.

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HbA1c Converter

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A clearer picture of your health starts with a single drop.