CGM Metrics, Monitoring & Planning Calculators

The glucose management indicator (GMI) estimates an A1c-like value from your CGM average glucose over a period such as 14 days, while A1c is a blood test reflecting roughly 2–3 months of glucose. They often differ slightly because they measure in different ways, and a consistent gap is useful information for your care team.

For most adults with type 1 or type 2 diabetes, the goal is more than 70% of time in the 70–180 mg/dL range, with under 4% below 70 mg/dL. Pregnancy and higher-risk groups use different targets, set with your care team.

International consensus targets for most adults are: time in range above 70%, time below 70 mg/dL under 4% (under 1% below 54), time above 180 mg/dL under 25%, a GMI under 7%, and glucose variability (CV) of 36% or less. Your individual goals may differ.

Some tools — GMI and time in range — work best with continuous glucose monitor data, while others use any inputs: eAG to A1c converts an A1c, the pump-settings, basal-percentage and carb-factor tools use your total daily dose, and pre-bolus timing uses a single glucose and trend. You can use most of them without a CGM.

Beyond reading your CGM, the planning tools translate your numbers into action: starting pump settings and basal share from your total daily dose, a carb factor for meals, a structured basal-rate test, and pre-bolus timing — and the pump-vs-MDI cost tool helps weigh delivery options. All are educational starting points to discuss with your care team.

The GKI combines blood glucose and blood ketones into one number to track the depth of nutritional ketosis, used with ketogenic diets and some metabolic and therapeutic protocols. It is not a way to assess diabetic ketoacidosis, which is a medical emergency.