A1C to Blood Sugar Calculator
Convert A1C percentage to estimated average glucose.
Estimated average glucose
114 mg/dL
Normal
In mmol/L
6.3
Diagnostic cutoffs
5.7% prediabetes · 6.5% diabetes
Educational conversion (ADA formula). Diagnosis requires repeat lab testing and clinical context.
Three months in one number
A1C measures the fraction of hemoglobin coated with glucose — since red cells live ~3 months, it integrates average blood sugar over that window. The eAG conversion (28.7 × A1C − 46.7) restates it in meter units: 5.6% ≈ 114 mg/dL.
Averages hide swings
Two people with identical A1C can have very different glucose stability — one steady, one swinging between highs and lows. That's why continuous glucose monitors report 'time in range' alongside A1C, and why symptoms with a normal A1C still merit a conversation.
Frequently asked questions
- How does the A1C to Blood Sugar Calculator work?
- Convert A1C percentage to estimated average glucose.
- Is the A1C to Blood Sugar Calculator free to use?
- Yes. The A1C to Blood Sugar Calculator is completely free, runs entirely in your browser, and requires no account or sign-up. Your inputs never leave your device.
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