Quick-reference table
| mg/dL | mmol/L | Where you might see it |
|---|---|---|
| 70 | 3.9 | Lower edge of typical fasting range |
| 100 | 5.6 | Common fasting reference point |
| 126 | 7.0 | Fasting threshold clinicians use for diabetes (repeat testing required) |
| 140 | 7.8 | Upper edge of where healthy people spend most time |
| 180 | 10.0 | Upper edge of the clinical time-in-range target in diabetes care |
| 200 | 11.1 | Random-reading threshold clinicians use, with symptoms |
Why two units exist
The US (and a handful of other countries) reports glucose as a weight per volume — milligrams per deciliter. Most of the world reports it as a molecular count — millimoles per liter. Same blood, same sugar, different rulers. The confusion mostly shows up in three places: reading research papers, using apps or CGMs set to the wrong region, and comparing notes in online communities where half the numbers look ten times bigger than the other half.
One companion number worth knowing: your lab's HbA1c percentage is a different measurement altogether — a three-month average, not a moment-in-time reading. To translate that into these units, use the HbA1c → average glucose calculator.
This converter is for education only. It converts units; it does not interpret results or replace medical advice. Discuss your readings with your healthcare provider.