Why are there two HbA1c units?

NGSP reports HbA1c as a percentage (%), used in the US and many countries. IFCC reports in mmol/mol, used in some international labs. Both represent the same measurement.

How do I convert between them?

Enter your value and select the unit you have. The calculator shows the equivalent in the other unit: mmol/mol = (HbA1c(%) − 2.15) × 10.929.

HbA1c Unit Converter (NGSP % to IFCC mmol/mol)

Convert HbA1c between NGSP (%) and IFCC (mmol/mol) units.

What this calculator does

This tool converts HbA1c between two common reporting units: NGSP (percent, used in the US and many countries) and IFCC (mmol/mol, used in some labs internationally). It is a reference conversion only.

What your result means

The result is the same HbA1c value expressed in the other unit. Use it to compare or report values when your lab uses a different unit. Interpretation of HbA1c for diabetes care should be done by your healthcare provider.

This is not medical advice. A healthcare provider should interpret results in your context.

HbA1c (%)

Key terms

NGSP: National Glycohemoglobin Standardization Program; the standard for reporting HbA1c as a percentage (%).
IFCC: International Federation of Clinical Chemistry; reports HbA1c in mmol/mol.
HbA1c (%): HbA1c in NGSP units; commonly used in the US and many countries.
HbA1c (mmol/mol): HbA1c in IFCC units; used in some international labs. Conversion: mmol/mol = (HbA1c(%) − 2.15) × 10.929.

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This tool is for educational and reference use only. It does not constitute medical advice. Always consult a healthcare professional for medical decisions.