A1C Calculator

An A1C is a lab result, not something you calculate from a meter. This calculator converts it: A1C = (average glucose in mg/dL + 46.7) / 28.7. An average glucose of 154 mg/dL gives an A1C of 7.0 percent. It is an estimate, and your lab result is the one to rely on.

The ADAG equation is eAG (mg/dL) = 28.7 x A1C - 46.7, so A1C = (eAG + 46.7) / 28.7. For example, an A1C of 7 percent gives 28.7 × 7 − 46.7 = 154.2 mg/dL, which is 8.6 mmol/L. The American Diabetes Association uses this equation in its conversion calculator.

An average glucose of 110 mg/dL converts to an A1C of 5.5 percent, which is below 5.7 percent, the lower edge of the prediabetes range. Remember this treats 110 as your average over about 3 months, not a single reading. A single reading is not an A1C.

An average glucose of 140 mg/dL converts to an A1C of 6.5 percent. That sits just at the 6.5 percent level NIDDK uses for diabetes diagnosis. A diagnosis needs a lab test and a clinician, so use this only as an estimate.

An average glucose of 100 mg/dL converts to an A1C of 5.1 percent, using (100 + 46.7) / 28.7. In mmol/L, 100 mg/dL is 5.6. The glucose table lists other values. This is an estimate from a published equation, and your measured A1C can differ.

An average glucose of 150 mg/dL converts to an A1C of 6.9 percent. Put another way, an A1C of 7 percent corresponds to an average of 154 mg/dL, so 150 is a little below that line. This is an estimate, and a lab result is the figure to rely on.

An average glucose of 180 mg/dL converts to an A1C of 7.9 percent. In mmol/L that is 10.0. The estimate comes from the ADAG equation and can differ from a measured A1C. Check the glucose unit first, because 180 in mmol/L would be a very different value.

Multiply the A1C by 28.7 and subtract 46.7 to get mg/dL, then divide by 18.016 for mmol/L. An A1C of 6 percent gives 125 mg/dL (7.0 mmol/L). Choose A1C mode in the calculator and it shows both units. The answer is an estimate of your average, not a measured value.

eAG stands for estimated average glucose. It restates an A1C in the same units, mg/dL or mmol/L, that people see on a glucose meter. The goal of the ADAG work was to make the A1C easier to relate to daily readings. It is an estimate, and your actual average can differ.

Use the NGSP master equation: IFCC (mmol/mol) = (A1C - 2.152) / 0.09148. An A1C of 7 percent is 53 mmol/mol, and 6.5 percent is 48. Choose A1C mode and the calculator shows the mmol/mol value. The conversion is exact to the rounding of the master equation, and it works in both directions.

Use NGSP = 0.09148 x IFCC + 2.152. For 48 mmol/mol that is 6.5 percent, and 53 mmol/mol is 7.0 percent. Choose the mmol/mol mode in the calculator for an instant conversion. The same equation works in reverse, so you can switch scales freely in either direction.

A1C is the percentage of hemoglobin with glucose attached, reflecting roughly the last 3 months. Average glucose is a mean of glucose readings in mg/dL or mmol/L. The ADAG equation links the two, but they are not identical, because each person's relationship differs a little.

According to NIDDK, the A1C test reflects your average blood glucose levels over the past 3 months. It is not a measure of a single day. A result is reported as a percentage of hemoglobin with glucose attached, and sometimes also as an estimated average glucose.

NIDDK lists an A1C below 5.7 percent as normal, 5.7 to 6.4 percent as prediabetes, and 6.5 percent or above as diabetes. These are diagnostic categories used by clinicians. This calculator converts values and does not diagnose, so discuss any result with a healthcare professional.

NIDDK lists 5.7 to 6.4 percent as prediabetes. In average glucose terms that is roughly 117 to 137 mg/dL by the ADAG equation. Only a clinician can say what a result means for you. The categories are used by clinicians and are not a diagnosis from this page.

NIDDK lists an A1C of 6.5 percent or above as diabetes. By the ADAG equation 6.5 percent matches an average glucose of about 140 mg/dL (7.8 mmol/L). A diagnosis needs a clinician and confirmatory testing, not a calculator. The category names come from NIDDK and are shown for reference only.

This calculator cannot say. The NIDDK ranges describe how a result is categorised: below 5.7 percent is normal. Whether a person is still considered to have diabetes is a clinical judgement that depends on history and treatment, so ask your care team.

NIDDK says some people with diabetes can reduce the risk of complications by keeping the A1C below 7 percent, and that a less strict target of 7 to 8 percent may suit others. The right target is individual, so agree it with your care team rather than using a general number.

There is no single figure by age. NIDDK describes a target below 7 percent for many people with diabetes, with less strict targets such as 7 to 8 percent where life expectancy is limited, severe low blood sugar is a risk, or complications are advanced. Your care team sets the goal.

NIDDK notes that less strict A1C targets, such as 7 to 8 percent, may be appropriate for people with limited life expectancy, a risk of severe low blood sugar or advanced complications. That depends on health, not age alone, so the target should be agreed with a clinician.

The A1C reflects glucose attached to red blood cells over about 3 months, while a meter average covers the readings you took. Few readings, missed times of day, and the way red blood cells age can all make them differ. The ADAG equation is an average relationship, not a personal one.

Yes. NIDDK lists hemoglobin variants, sickle cell disease, iron-deficiency anemia, kidney and liver disease, recent blood transfusions or hemodialysis, and pregnancy. If one applies, your clinician may use other tests. The reliability table lists them. Ask your healthcare professional whether any of these could apply to you.

The conversion is an average relationship from a research study, so individual results can differ from the estimate. Treat eAG as a way to put an A1C in familiar units, not a precise measurement of your average. Your measured A1C and your care team's advice come first.

This calculator cannot say how often you should test, because that depends on your situation. The test reflects about 3 months of glucose, so changes take weeks to show up. Ask your care team how often to have it done.

Divide mg/dL by 18.016. A glucose of 126 mg/dL is 7.0 mmol/L. To go the other way, multiply mmol/L by 18.016, so 10 mmol/L is 180 mg/dL. The unit table lists common values, and the calculator accepts either unit. Always check which unit your meter or lab report uses before entering a number.

An average glucose of 10 mmol/L is 180.2 mg/dL, which converts to an A1C of 7.9 percent. Choose the glucose mode, set the unit to mmol/L and enter 10 to see it with the other units. The conversion applies to an average, not a single reading, so treat it as an estimate.

No. It converts between units using published equations and does not diagnose, treat or advise. Only a clinician can diagnose diabetes, using laboratory tests. Use the result to understand a number you already have, and talk to a healthcare professional about what it means.

The conversion only covers A1C values from 3 to 20 percent. An average glucose or mmol/mol value that implies an A1C outside that range is rejected, because the equation was not meant for it. Check the unit you selected if you see this message.

Choose what you have: an A1C percentage, an average glucose in mg/dL or mmol/L, or an IFCC value in mmol/mol. Enter it and the calculator shows the A1C, the estimated average glucose in both units and the mmol/mol value. It is an estimate, not a diagnosis.