What is calculated
Estimated average glucose corresponding to a laboratory A1C.
A1C to Estimated Average Glucose Calculator
A1C and average glucose estimate
Enter your values, then calculate to see a verified result.
Reference range
How this result is calculated
A clear calculation path based on your inputs.
Inputs usedReview the information used for this result.
Full calculation and sourcesOpen Full calculation and sources to review the formula, assumptions, boundaries, and evidence.
Versioned calculationFormula v1.1.0
Method
Apply the NGSP/ADAG regression equation.
Important boundary
Conditions affecting red blood cells or A1C accuracy can make the estimate misleading.
Enter laboratory A1CUse the labeled input and matching unit.
Measured or label valueApply the ADAG equationThe calculator applies the stated equation.
Full precision firstKeep uncertainty visibleKeep the boundary beside the result.
Reference, not diagnosisInterpretation
mg/dL is the regression estimate.
The mmol/L equivalent stays visible.
Do not change treatment from this calculator alone.
Use this result
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Related calculators and resources
Method and test recordFormula v1.1.0
- Recorded scope
- health-wellness-completion
- Publisher
- CalculatorGeek
- Recorded review date
- 2026-10-05
- Next source review
- 2027-04-05
- Definition fixtures
- 3 configured scenarios
- Published examples
- 3 shown below
Recorded method
Verify ADAG regression and mg/dL-to-mmol/L conversion.
These records describe the published model and reference tests. A test-case count is not a certification of every possible input or an independent specialist review. Editorial policy
Known limitations
- A1C can be affected by anemia, kidney failure, liver disease, hemoglobin variants, transfusion, blood loss, medicines, and pregnancy.
- eAG is not a direct glucose measurement.
- Does not show glucose variability or hypoglycemia.
Method sources
Latest model update
2026-10-05 - Initial evidence-limited shared-system implementation with fixtures, original support content, and contextual links.
Reference inputs and expected results
Up to 12 examples from the configured definition fixtures are shown. Expected values use the stated output units; invalid inputs are intended to be rejected.
| Case | Inputs | Expected result |
|---|---|---|
| seven percent A1C | Convert: a1c_to_eag; Laboratory A1C: 7 percent | Estimated average glucose: 154.2 mg/dL; Estimated average glucose: 8.55810856 mmol/L (allowed numeric tolerance: 0.001) |
| six percent A1C | Convert: a1c_to_eag; Laboratory A1C: 6 percent | Estimated average glucose: 125.5 mg/dL (allowed numeric tolerance: 0.0001) |
| Average glucose reverse estimate | Convert: eag_to_a1c; Average glucose: 125.5 mg/dL | a1c_value: 6; Estimated average glucose: 125.5 mg/dL; IFCC equivalent: 42.0638390905 mmol/mol (allowed numeric tolerance: 1.0E-6) |
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On this page
What the A1C to Estimated Average Glucose Calculator calculates
Convert a laboratory A1C percentage into NGSP/ADAG estimated average glucose in mg/dL and mmol/L.
The page keeps estimated average glucose distinct from a directly measured glucose average.
Continue this workflow with the CDC Prediabetes Risk Test. Apply the official CDC screening score.
How to use the A1C to Estimated Average Glucose Calculator
- Enter laboratory A1C as a percentage.
- Read eAG in both common units.
- Compare only with appropriately collected glucose data.
- Consider known A1C limitations.
Continue with the A1C Calculator. Convert A1C into estimated average glucose.
Formula, variables and calculation order
eAG mg/dL = 28.7 x A1C - 46.7; eAG mmol/L = mg/dL / 18.018.
Inputs are validated and normalized before calculation. Full precision is retained until the displayed result is rounded.
Cross-check a different part of the decision with the Blood Pressure Calculator. Classify a measured systolic and diastolic pair.
Worked example and boundary check
Worked example
An A1C of 7.0% corresponds to about 154 mg/dL or 8.6 mmol/L.
Boundary check
The regression has biological scatter and does not reproduce daily highs, lows, or timing.
How to interpret the result
Use the result to translate units and improve discussion. Diagnosis, goals, and treatment remain clinical decisions.
- A1C can be affected by anemia, kidney failure, liver disease, hemoglobin variants, transfusion, blood loss, medicines, and pregnancy.
- eAG is not a direct glucose measurement.
- Does not show glucose variability or hypoglycemia.
For a separate result with different assumptions, open the Cholesterol Ratio Calculator. Calculate common lipid ratios without diagnosing disease.
Frequently asked questions
Is eAG my exact average?
No. It is a regression estimate.
Why does my CGM average differ?
Measurement periods, missing data, biology, and A1C limitations can create differences.
Can this diagnose diabetes?
No.
What equation is used?
The NGSP/ADAG relationship shown on the page.
Primary sources and evidence limits
Sources were checked 2026-10-05. A reference value, conversion, or schedule estimate is not a diagnosis, prescription, individualized treatment target, or substitute for professional care.