The ICR tells you how many grams of carbohydrate are covered by 1 unit of rapid-acting insulin. It is used to calculate mealtime (bolus) insulin doses. The "500 Rule" is the most common starting formula for rapid-acting insulin analogues (lispro, aspart, glulisine).
Add all insulin: basal + all bolus doses over a typical 24-hour period.
How to use your ICR: Mealtime dose = (Carbohydrates in meal ÷ ICR)
Example: If ICR = 10, and meal has 60g carbs → give 6 units pre-meal
⚕️ Important: This calculator provides a starting estimate only. Your actual ICR may vary by time of day (often different at breakfast vs. dinner), stress level, activity, and illness. ICR should always be confirmed and adjusted by your diabetes care team based on blood glucose response. Never adjust insulin doses without guidance from your provider.