Time in Range for Diabetes Management with CGM - Updated

Dexcom CGM user checking his glucose levels

The CGM Blog

Breaking Down Time in Range:
A New Way to Think About Glucose

Updated for 2025

Time in range, or TIR, is a glucose monitoring metric that can give you and your diabetes care team a better understanding of how well your glucose management habits are working. Learning more about time in range can help you use it to guide your glucose management. This can be especially helpful if you’re new to using a continuous glucose monitoring (CGM) system.

What is time in range (TIR) for diabetes?

Time in range (TIR) is the amount of time your blood sugar, or glucose, level, is within the range you and your doctor have determined will best support your overall health. TIR also reflects how much time you spend experiencing hypoglycemia, or low glucose, and hyperglycemia, or high glucose. Diabetes Canada generally recommends that adults living with diabetes keep their glucose between 3.9 mmol/L and 10.0 mmol/L as often as possible. You and your doctor will work together to determine your ideal glucose range and how much time you should aim to spend within that range.

You can track your TIR using a CGM system like the Dexcom G7 CGM System. CGM technology makes it possible to take glucose readings continuously throughout the day and night without routine fingersticks,^* providing a complete picture of how much time you spend in range. Dexcom G7 can take glucose readings around every 5 minutes, which adds up to over 280 readings each day. If you’re using a blood glucose meter (BGM) to monitor your glucose, it’s not possible to take enough readings to get an accurate TIR.

TIR vs. A1C

In the clinic, doctors measure glucose control using an A1C test, which shows what your average glucose levels have been over the previous three months.1 While A1C gives doctors a general idea of how well your diabetes treatment plan is working overall, TIR can reveal whether your glucose levels are generally steady or if you’re experiencing a rollercoaster of highs and lows.^1,2

Think about the difference between TIR and A1C like tracking snowy weather. A1C is like the average yearly snowfall. If your town had an average snowfall of 300 cm last year, that number doesn’t tell you if it snowed more in December or January, or if there was a random snowstorm in May. Similarly, A1C can’t show you when you go above or below your glucose target range, or for how long. TIR is more like a daily or weekly weather report. It can reveal how often your glucose is in range and how often it’s high or low.

How tracking TIR can help support better glucose management

Tracking your TIR gives you the opportunity to learn more about what impacts your glucose levels so that you can take proactive action to stay in your ideal range more often. With Dexcom G7, you can view your TIR at a glance and see which days you spend the most time in range. Dexcom G7 also makes it easy to log your meals, activities, and insulin doses so you can make the connection between your TIR and your healthy choices. With this insight, you and your diabetes care team can make adjustments to your diabetes management routine to help you increase your TIR.

Spending more time in your ideal glucose range can help you improve your A1C.^3,4 Keeping your glucose levels in range for about 17 hours per day roughly equates to an A1C of 7.0%—which is the target A1C Diabetes Canada suggests for those living with diabetes.^3,4,5 Generally, the greater your TIR, the lower your A1C. For every two and a half hours more you spend in range each day, you can lower your A1C by about 0.5% to 0.8%.^4,6,7For example, if your current A1C is 8.5%, that can mean a drop to somewhere between 8.0% and 7.7%.

Lowering your A1C can help reduce the risk of serious diabetes complications such as nerve, vision, or organ damage and cardiovascular disease.⁴Working to keep your glucose levels stable can also help you feel your best, so you can focus on enjoying the things that matter most to you.

How much time should you spend in your target glucose range?

Diabetes affects every body differently. You’ll work with your doctor to determine a realistic TIR goal that supports your diabetes management plan. As you get older or if you experience diabetes complications, your glucose management goals might change. It’s important to attend your regular check-ups to ensure that your ideal glucose range and TIR targets are right for where you’re at in your diabetes journey.

Here are the general TIR targets determined by the International Consensus on Time in Range to give you an idea of how much time you should spend in your ideal glucose range each day:5

Stay in your ideal glucose range more often with Dexcom G7

Dexcom CGM Systems, including Dexcom G7, are clinically proven to help people living with diabetes lower their A1C, reduce hypoglycemia, and spend more time in their ideal glucose range.^8-13

With Dexcom G7, you can view your glucose levels on your compatible smartphone or smartwatch or handheld receiver and get the insights you need to make more informed, proactive decisions that support your glucose goals.^† Dexcom G7 can provide a predictive alert up to 20 minutes before your glucose is likely to go below 3.1 mmol/L so you can take action to prevent lows and stay in range.^{‡ 14}

At your regular appointments, you and your diabetes care team can review past glucose readings using Dexcom Clarity reports, available right in the Dexcom G7 app. If you’re using a receiver, you can check your TIR and other meaningful glucose metrics under the Reports section and find more detailed reports in the Dexcom Clarity app. Dexcom Clarity gives you insight into patterns in your glucose and can automatically identify important trends like low glucose overnight. This can help you pinpoint which aspects of your diabetes management routine help you stay in range. You can also see when you’ve hit your TIR goals with your Best Glucose Day, giving you the chance to celebrate your hard work!

Explore how Dexcom G7 can support your glucose management

* If your glucose alerts and readings from the G6 do not match symptoms or expectations, use a blood glucose meter to make diabetes treatment decisions.
† Smart devices sold separately. For a list of compatible devices, please visit dexcom.com/compatibility.
‡ This predictive alert can be triggered with impending hypoglycemia (glucose of 3.1 mmol/L or below is predicted to occur within the next 20 minutes).

1 A1C. Cleveland Clinic. Reviewed November 22, 2022. Accessed July 15, 2025. https://my.clevelandclinic.org/health/diagnostics/9731-a1c
2 Time in Range. Breakthrough T1D. Accessed July 15, 2025. https://breakthrought1d.ca/time-in-range/
3 Imran AS, et. al. Can J Diabetes. 2018:42(S42–S46).
4 Cheng AYY, et al. Can J Diabetes. 2021;45(7):580-587.
5 Battelino T, et al. Diabetes Care. 2019;42(8):1593-1603.
6 Beck RW, et al. J Diabetes Sci Technol. 2019;13(4):614-626.
7 Vigersky RA, et al. Diabetes Technol Ther. 2019;21(2):81-85.
8 Beck RW, et al. JAMA. 2017;317(4):371-378.
9 Beck RW, et al. Ann Intern Med. 2017;167(6):365-374.
10 Martens T, et al. JAMA. 2021;325(22):2262-2272.
11 Laffel LM, et al. JAMA. 2020;323(23):2388-2396.
12 Wels JB, et al. J Diabetes Sci Technol. 2024;18(1):143-7.
13 Heinemann L, et al. Lancet. 2018;391(10128):1367-1377.
14 Preechasuk L, et al. Diabetes Technol Ther. 2024;26(7):498-502.