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Getting ready for an A1C test: what it is, the numbers, what can change them, and your goal
For anyone sent for an A1C blood test (also called hemoglobin A1C or HbA1c), or holding a result they cannot read: for prediabetes, type 2 diabetes, or managing diabetes. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK, part of the NIH) says the A1C test gives information about your average blood glucose, also called blood sugar, over the past 3 months. This page passes on, by name, what NIDDK says: what the test measures, and that you don’t have to fast for it; the numbers NIDDK gives for prediabetes and diabetes, and why a second test confirms them; pregnancy and the other blood glucose tests; why results can differ, and what can make an A1C wrong, from anemia and sickle cell to hemoglobin variants; and goals after a diagnosis. It builds the words to say and the questions to ask, and prints a card for the fridge with a line for your number.
Right now
- Trouble breathing, chest pain, or fainting, or someone with diabetes who passes out or cannot swallow? Call 911 (ours).
- Someone with diabetes who is shaky, sweaty or confused? Our diabetes page has the steps for low blood sugar (ours).
- A high result, and you take medicine for diabetes? Do not stop or change a prescribed medicine on your own; ask your team (ours).
- Scared of what the number means, or thinking of ending your life? Call or text 988, any hour (ours).
More help
- Blood sugar, on this site: Prediabetes · Diabetes · Blood sugar log · Heart, blood and hormones: find the right page.
- Your blood: Anemia and low iron · Sickle cell disease and the trait.
- Getting ready: My medicines list · Get ready for your appointment.
- Care and costs: When you need a doctor and can’t pay · Medical bills.
- In a crisis: Help right now (988, 911). All our free tools.
Your heart, blood pressure, blood sugar, thyroid or blood, and not sure this is the right page? The pages on this site for a heart attack or stroke, blood pressure, AFib, heart failure, cholesterol, diabetes and prediabetes, the thyroid, anemia, sickle cell and menopause, on one list.
Another test coming up, or not sure this is the right page? The guides on this site for a colonoscopy, an endoscopy, a GI series, ERCP, a biopsy, a cystoscopy, urodynamic tests, urinary tract imaging, prostate tests, an A1C and thyroid tests, on one list.
Other guides on this site that go with this page
Free to read. We chose these ourselves; no professional did. Each guide was written with AI and has not been reviewed by a professional. They are general information, not advice.
- Diabetes and your mouth: gum disease, dry mouth, the signs to check for, the dentist, and the cost: diabetes and your mouth: how diabetes changes your saliva, gum disease (gingivitis and periodontitis), dry mouth and the other mouth problems, the signs to check for, what to tell your dentist, getting ready for dental work, and keeping your mouth healthy when money is tight.
- Diabetes and pregnancy: getting ready, the risks, the blood glucose targets, insulin, and after the baby: diabetes and pregnancy (type 1 or type 2 diabetes, pregnant or planning a pregnancy): getting ready, the risks for the baby and you, the blood glucose targets, insulin and medicines, and after the baby.
- Diabetes, heart disease, and stroke: what raises the risk, the warning signs, the ABCs, and the medicines: diabetes, heart disease and stroke: why diabetes raises the risk, what else adds to it, the warning signs of a heart attack and a stroke, how doctors check your heart, aspirin, statins and the medicines to ask about, and your diabetes ABCs.
- Diabetes, sexual and bladder problems: erection trouble, dryness and pain, leaks, trouble going, infections, and what helps: diabetes, sexual and bladder problems: why diabetes can change sex and the bladder, erection problems, low desire, dryness and painful sex, yeast and bladder infections, leaks, trouble going, and what helps.
- Diabetes and your feet: how diabetes can hurt your feet, the daily foot care that protects them, shoes and socks, and when to call the doctor: diabetes and your feet: how diabetes can hurt your feet, checking and washing them every day, corns and toenails, shoes and socks, and when to call the doctor.
- Monogenic diabetes (MODY and neonatal diabetes): diabetes caused by a change in one gene, who gets it, the genetic test, families, and treatment: monogenic diabetes (MODY and neonatal diabetes): diabetes caused by a change in one gene, the genetic test, families, and treatment.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor or nurse has reviewed it. The facts were read on October 18, 2026 on NIDDK’s The A1C Test & Diabetes page (NIH), last reviewed in April 2018, and its Spanish version, last reviewed in April 2019; they say the same things. The cards also point to NIDDK’s Diabetes Tests & Diagnosis, Risk Factors for Type 2 Diabetes and The A1C Test & Race/Ethnicity pages. The numbers (the past 3 months; below 5.7, 5.7 to 6.4, and 6.5 percent or above; fasting at least 8 hours for the other tests; 24 to 28 weeks; no later than 12 weeks after the baby is born, then every 3 years; 6.8 reported from 6.4 to 7.2; at least twice a year; below 7, and 7 to 8 percent; the past 30 days) are NIDDK’s. Ours: 911 for trouble breathing, chest pain, or fainting, or someone with diabetes who passes out or cannot swallow; pointing to our diabetes page for low blood sugar; never stopping or changing a prescribed medicine on your own; asking which test it is and whether to fast; writing your number and the date on the card; asking whether the blood went to a lab and when the second test is; telling them about anemia, sickle cell, kidney or liver disease, blood loss, a transfusion or dialysis, and your family’s descent; asking what your own goal is; the card; 988 when it is too much; health centers when money is tight; and the order of the steps. What we left out: brands and doses, the eAG conversion table, the clinical trials section, and the references. This page saves nothing and loads no trackers.