Time in Range (TIR) refers to the percentage of time that a person's glucose levels stay within a defined target range. It is a key indicator for assessing the quality of glucose control, typically based on data collected from continuous glucose monitoring (CGM) devices.

TIR reflects the proportion of time that glucose levels fall into three general categories:

• Target Range: 3.9–10.0 mmol/L
• Very High: Above 13.9 mmol/L
• Very Low: Below 3.0 mmol/L

These thresholds are based on international clinical consensus, but doctors may adjust them according to individual needs.

Why is TIR important?

• TIR provides a more dynamic view of daily glucose control than A1C alone.
• Maintaining a higher TIR (e.g., above 70%) is associated with reduced risk of complications.
• TIR is useful for evaluating treatment effectiveness, medication response, or lifestyle changes.

TIR is becoming a standard metric in diabetes management and supports more personalized, real-time care.