A1C Calculator

Enter Average blood glucose, Unit and Calculation type to review a1c with this tool. The relationship describes an estimated average, not the value expected at every glucose check.

✏️ Enter your glucose value

📊 Your A1c position

Normal
<5.7% Prediabetes
5.7-6.4% Diabetes
≥6.5%
-

🩸 Your A1c results

✅
Your A1c
0.0%
Normal range
eAG 0
Category -
Status -
0%
A1c
0
eAG (mg/dL)

📊 Glucose tracking guide

Target Fasting Post-Meal
Normal < 100 mg/dL < 140 mg/dL
Prediabetes 100-125 mg/dL 140-199 mg/dL
Diabetes ≥ 126 mg/dL ≥ 200 mg/dL
Your eAG - -

📖 Result Details

🩸 A1c Value
-
-
Normal: < 5.7%
📊 eAG (Avg Glucose)
-
-
Normal: < 117 mg/dL
🏷️ Category
-
-
Based on A1c guidelines

Formula Used

eAG (mg/dL) = 28.7 × A1C (%) − 46.7; mmol/L = mg/dL ÷ 18.

Model assumptions: Population-based estimate; individual A1C and measured average glucose can differ.

References: NGSP A1C/eAG conversion

How the formula is applied

The calculation links Average blood glucose, Unit and Calculation type to a1c. The relationship describes an estimated average, not the value expected at every glucose check. The mg/dL and mmol/L displays express the same modeled average on different scales. Model convention: Population-based estimate; individual A1C and measured average glucose can differ.

Calculator Description

Enter Average blood glucose, Unit and Calculation type to review a1c with this tool. The relationship describes an estimated average, not the value expected at every glucose check.

Translate between an A1C percentage and estimated average glucose to understand how the two reporting scales relate. Check the unit before comparing the estimate with a glucose log.

The relationship describes an estimated average, not the value expected at every glucose check. The mg/dL and mmol/L displays express the same modeled average on different scales.

Frequently Asked Questions

What information do I need for the A1C Calculator?

Prepare Average blood glucose, Unit and Calculation type. Choose the conversion direction and enter either the A1C percentage or average-glucose unit requested.

Is an estimated A1C the same as a laboratory result?

The relationship describes an estimated average, not the value expected at every glucose check. The mg/dL and mmol/L displays express the same modeled average on different scales. Individual A1C-to-glucose relationships can differ. Conditions affecting red blood cells and other clinical factors can affect interpretation; the conversion cannot diagnose diabetes.

How can I check the a1c calculator with an example?

Use the full settings in the worked-example table. They produce A1c: 6.5%. Compare the method and units as well as the displayed number.

Which assumptions apply to this a1c calculator?

Population-based estimate; individual A1C and measured average glucose can differ. Choose the conversion direction and enter either the A1C percentage or average-glucose unit requested.

When should I verify the a1c calculator result elsewhere?

Individual A1C-to-glucose relationships can differ. Conditions affecting red blood cells and other clinical factors can affect interpretation; the conversion cannot diagnose diabetes. For personal care, discuss the measurements and method with a qualified clinician.

How to Use This Calculator

  1. Choose the conversion direction and enter either the A1C percentage or average-glucose unit requested.
  2. Fill in Average blood glucose, Unit and Calculation type. Use the field units rather than copying an unlabeled value.
  3. For a result check, reproduce the example beginning with Average blood glucose = 140 and Unit = mg/dL; copy the remaining settings from the detailed guide.
  4. Use the page's Calculate or Convert control, or read the updated result where the tool recalculates automatically. Locate A1c and any supporting breakdown.
  5. Interpret the result with this distinction in mind: The relationship describes an estimated average, not the value expected at every glucose check. Keep the selected inputs alongside the output when comparing scenarios.

Practical example and result check

Worked a1c calculator example. Set Average blood glucose = 140; Unit = mg/dL; Calculation type = eAG → A1c. The corresponding output is A1c: 6.5%. The relationship describes an estimated average, not the value expected at every glucose check.

Before relying on the result

  • Confirm the units, dates, rates and time periods entered.
  • Review which costs, measurements or assumptions are included and excluded.
  • Change one important input at a time to understand the result sensitivity.

Detailed Calculator Guide

Choose the right question for A1C Calculator

Translate between an A1C percentage and estimated average glucose to understand how the two reporting scales relate. Check the unit before comparing the estimate with a glucose log.

Prepare the inputs

Choose the conversion direction and enter either the A1C percentage or average-glucose unit requested.

A1C Calculator: worked input settings
FieldExample valueEntry check
Average blood glucose140Use the stated unit and the measurement required by this model.
Unitmg/dLConfirm the unit or currency selection before reading the converted value.
Calculation typeeAG → A1cSelect the method before interpreting the result; different modes answer different questions.

Follow the calculation

Relationship used for this example: eAG (mg/dL) = 28.7 × A1C (%) − 46.7; mmol/L = mg/dL ÷ 18.

The relationship describes an estimated average, not the value expected at every glucose check. The mg/dL and mmol/L displays express the same modeled average on different scales.

Assumptions for this model: Population-based estimate; individual A1C and measured average glucose can differ.

Read the worked result

Results for the worked settings
OutputDisplayed result
A1c6.5%

With these settings, a1c is 6.5%. Use the same units and calculation mode when reproducing this example.

Is an estimated A1C the same as a laboratory result?

The relationship describes an estimated average, not the value expected at every glucose check. The mg/dL and mmol/L displays express the same modeled average on different scales. Individual A1C-to-glucose relationships can differ. Conditions affecting red blood cells and other clinical factors can affect interpretation; the conversion cannot diagnose diabetes.

Apply the result to your own scenario

Replace the illustrative average blood glucose value (140) with your own value, then complete the other inputs for the same scenario. Choose the conversion direction and enter either the A1C percentage or average-glucose unit requested.

Sources and method notes

Supporting Guides

Health Measurement Accuracy GuideImprove consistency when entering weight, height, circumference, heart rate and other health measurements.How to Interpret Health Calculator EstimatesUnderstand screening values, ranges, uncertainty and the limits of online health calculations.When a Calculator Result Needs Professional ReviewRecognize situations where symptoms, abnormal results or treatment decisions require a qualified clinician.