Time in range calculator

Time in range is the share of your readings between two lines. The international consensus band is 70–180 mg/dL (3.9–10.0 mmol/L), with a goal above 70% for people with diabetes; adults without diabetes spent about 96% of the time between 70 and 140 mg/dL (3.9–7.8 mmol/L) in one study (Shah et al. 2019).

Unit

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How it is worked out

Time in range = readings from 70 to 180 mg/dL (inclusive) ÷ all readings Hours a day = time in range × 24

Counted by readings, the way CGM software does, so it assumes your readings are evenly spaced. Below 70 includes below 54; above 180 includes above 250. Consensus targets for people with diabetes: more than 70% in 70–180, less than 4% below 70, less than 25% above 180 (Battelino et al. 2019).

Sources

  1. Battelino et al. 2019. Diabetes Care 42(8):1593-1603. International consensus on time in range.
  2. Shah et al. 2019. Journal of Clinical Endocrinology & Metabolism 104(10):4356-4364. CGM profiles in 153 healthy participants without diabetes.
  3. Spartano et al. 2024. Journal of Clinical Endocrinology & Metabolism. CGM in the Framingham Heart Study.

Glucose tools

See it all from your export

The free CGM report reads the whole file: your 24-hour profile (AGP), time in range, GMI, variability, your biggest rises and overnight sensor pressure.

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Questions people ask

How do I calculate time in range from my CGM readings?
Count the readings between 70 and 180 mg/dL (3.9–10.0 mmol/L), divide by all your readings and multiply by 100. Paste your readings or drop your export above and it is done for you, along with time below and above and the same on the tighter 70–140 band.
What is a normal time in range without diabetes?
In a study of 153 adults and children without diabetes, the median time between 70 and 140 mg/dL was 96% (Shah et al. 2019). In the larger Framingham study, adults without diabetes spent about 3 hours a day above 140 mg/dL (Spartano et al. 2024). Sensors and people differ, so treat these as context, not a pass mark.
What does 70% time in range mean in hours?
70% of the day is 16 hours 48 minutes. Each 1% of time in range is about 14 minutes a day.
Why are there two ranges?
The 70–180 mg/dL band was set by an international consensus for people with diabetes. People without diabetes spend almost all day below 140, so a tighter 70–140 band shows more of their day-to-day changes.

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Information, not a diagnosis. HealthOS is a wellness product, not a medical device: these numbers can’t tell you whether anything needs treatment. Talk to a doctor about your results.