Insulin-to-Carb Ratio Calculator
Mealtime bolus from carbohydrates, plus an optional correction dose.
Carbohydrate (meal) dose
Enter carbs and the I:C ratio to calculate the meal dose.
Correction dose
OptionalThe correction factor (insulin sensitivity factor) is how many mg/dL one unit lowers glucose. Leave blank to calculate the meal dose only.
Enter at least the carbs and I:C ratio to see the total.
How the pieces fit
The insulin-to-carb ratio covers the carbohydrates in the meal (1 unit per X grams). The correction factor (insulin sensitivity factor) brings a high glucose back toward target. Mealtime dose = meal coverage + correction.
Ratios and factors are individualized and provider-ordered— they differ by patient, by meal, and by time of day. Rounding conventions vary by facility and device; this tool rounds to the nearest half unit and shows the exact value. Always confirm against the order and the patient’s own regimen.
Educational use only. Insulin dosing is an individualized provider order. This tool illustrates the standard arithmetic only — it does not set ratios, targets, or correction factors, and is not a substitute for the prescribed regimen or independent double-check. This material supports nursing education and exam review. It is not medical advice and is not a substitute for clinical judgment, institutional policy, or medical direction. Always follow facility protocols and current provider orders.