Blood Glucose 6 tested - mmol/L or mg/dL?
Most meters outside the US show mmol/L. A reading of 6 is far more likely to be 6 mmol/L than 6 mg/dL.
If it is 6 mmol/L
= 108 mg/dL. Fasting without diabetes: Prediabetes range · With diabetes before a meal: In target
Full explanation for 108 mg/dL →If it really is 6 mg/dL
That is 0.3 mmol/L — severely low, below the level 2 hypoglycemia threshold of 54 mg/dL (3.0 mmol/L). Most meters show "LO" below 20 mg/dL. If the person is shaky, sweaty, confused or drowsy, treat it as a severe low: 15–20 g of fast-acting carbohydrate if they can swallow safely; if not, glucagon if available, recovery position and call 911 (US) or your local emergency number.
Full explanation for 6 mg/dL →Not urgent — but follow up
- Without diabetes: as a fasting reading this is in the prediabetes range — ask your doctor for an HbA1c or a repeat fasting test. After a meal it is normal.
- With diabetes: in target — nothing to change.
- Note the time and whether you had eaten — the same number means different things fasting and after a meal.
If you don't have diabetes — reading 6 mmol/L (108 mg/dL)
Fasting, 6 mmol/L (108 mg/dL) is in the prediabetes range (5.6–6.9 mmol/L = 100–125 mg/dL). After a meal it is normal. If this was a true fasting reading, ask your doctor for an HbA1c or a repeat fasting test — prediabetes is common and very often reversible.
Fasting prediabetes cut-off: the ADA uses 5.6 mmol/L (100 mg/dL); the WHO uses 6.1 mmol/L (110 mg/dL). This site follows the ADA.
Fasting (8+ hours without food)
Prediabetes range2 hours after eating (or glucose tolerance test)
NormalIf you have diabetes — reading 6 mmol/L (108 mg/dL)
6 mmol/L (108 mg/dL) is in target both before and after meals for most adults with diabetes (pre-meal 4.4–7.2 mmol/L = 80–130 mg/dL, after meals below 10.0 mmol/L = 180 mg/dL).
Before a meal / fasting
In target1–2 hours after a meal
In targetTargets for most non-pregnant adults (American Diabetes Association (ADA) Standards of Care). Your own targets may be different — for example in pregnancy, for children, older adults or people prone to lows. See pregnancy targets.
108 mg/dL as an average: HbA1c 5.4%
If 108 mg/dL were your average glucose over two to three months, it would match an HbA1c of about 5.4% (normal range). A single reading says little about your HbA1c — it is the long-term average that counts. Learn more in how to measure blood sugar.
Make sure the number is right
- Wash and dry your hands before a finger-stick: fruit juice or sugar on the skin can raise the result a lot.
- Home meters may differ from a lab value by up to about 15%. At 108 mg/dL that means roughly 92–124 mg/dL.
- CGM sensors measure tissue fluid and lag 5–15 minutes behind blood when glucose changes quickly — confirm lows with a finger-stick.
Check another reading
Nearby values
Sources: ADA Standards of Care · ADAG study (HbA1c and average glucose) · WHO: Definition and diagnosis of diabetes · MedlinePlus: Blood glucose test
This page explains one reading in general terms. It is not a diagnosis or a treatment instruction. Follow the plan agreed with your doctor or diabetes team.