FASTING PLASMA GLUCOSEFPG
Measured after at least 8 hours without calories. This is a laboratory diagnostic test, not simply any morning home-meter reading.
- Normal
- Below 100 mg/dL
- Prediabetes
- 100–125 mg/dL
- Diabetes
- 126 mg/dL or higher
GLUCOSE REF 01
Clear ranges.
Better questions.
This page puts common diagnostic glucose reference categories in one place so you can understand the terms a little better before speaking with a qualified healthcare professional.
This is education, not diagnosis.
A home reading, a single result, or this page cannot diagnose diabetes or replace care from a clinician. Testing methods, personal targets, pregnancy, medication, symptoms, and health history all matter. If you have symptoms or a result that worries you, contact a healthcare professional promptly.
CHECK A NUMBER 02
Compare a reference category.
Select the laboratory test type. This tool compares the number only against the American Diabetes Association’s public diagnostic categories; it does not interpret a personal health situation.
THE REFERENCE 03
Know which test
you are looking at.
2-HOUR ORAL GLUCOSE TOLERANCE TESTOGTT
Measured two hours after a 75-gram glucose drink in a clinical testing setting. It is different from an ordinary after-meal home reading.
- Normal
- Below 140 mg/dL
- Prediabetes
- 140–199 mg/dL
- Diabetes
- 200 mg/dL or higher
CONTEXT MATTERS 04
A number only means
something in context.
Diagnosis needs proper testing. The ADA explains that a diagnosis is normally made using healthcare-setting testing and typically needs confirmation on another day unless certain symptoms and very high glucose are present.
Personal targets are different. People already managing diabetes may receive individual glucose targets from their care team. Those targets should not be mixed up with the diagnostic categories shown here.
When in doubt, ask. Bring the test type, timing, result, medications, and any symptoms to your clinician. That gives them a much better picture than a number alone.
SOURCES 05
Built to be useful and responsible.
The reference categories on this page are based on the American Diabetes Association’s public diabetes diagnosis information. Read the original sources for full context.