Insulin Dose Calculator

What Is an Insulin Dose Calculator?

An insulin dose calculator is a tool that helps people with diabetes calculate the correct amount of rapid-acting insulin needed before meals. The calculation takes into account the amount of carbohydrates in a meal, the individual's insulin-to-carb ratio, their current blood glucose level, and their personal correction factor.

Key Components of the Calculation

• Insulin-to-Carbohydrate Ratio (ICR): How many grams of carbs are covered by 1 unit of insulin.
• Correction Factor (Sensitivity): How much 1 unit of insulin lowers your blood glucose.
• Target Blood Glucose: Your desired pre-meal blood glucose level (e.g., 100 mg/dL).
• Current Blood Glucose: Your actual reading before the meal.
• Carbohydrate Intake: Estimated grams of carbs in your upcoming meal.

How the Calculator Works

The total insulin dose is calculated as the sum of two parts:

Component	Formula	Description
Carb Dose	Carbs ÷ ICR	Insulin needed for food
Correction Dose	(Current BG − Target BG) ÷ Correction Factor	Insulin needed to bring blood sugar to target
Total Dose	Carb Dose + Correction Dose	Overall insulin to inject before the meal

Example

• ICR = 15 (1 unit covers 15g carbs)
• Correction Factor = 50 (1 unit drops 50 mg/dL)
• Target BG = 100 mg/dL
• Current BG = 150 mg/dL
• Carb Intake = 60g

Carb Dose = 60 ÷ 15 = 4 units
Correction Dose = (150 − 100) ÷ 50 = 1 unit
Total Dose = 5 units

Important Considerations

• This calculator assumes you're using fast-acting insulin like Lispro or Aspart.
• Always round doses as per your doctor’s advice.
• Never make dose changes without consulting your diabetes care team.

How to Use the Insulin Dose Calculator

This calculator helps you determine the appropriate mealtime insulin dose based on your carbohydrate intake and current blood glucose level. It uses two components:

• Carbohydrate Dose – to cover food intake
• Correction Dose – to adjust for high blood glucose, if needed

Step-by-Step Instructions

1. Enter your Insulin-to-Carb Ratio:
   This is how many grams of carbohydrates are covered by 1 unit of insulin. For example, if your ratio is 15, it means 1 unit covers 15g of carbs.
2. Enter your Correction Factor (Insulin Sensitivity):
   This is how much 1 unit of insulin is expected to lower your blood glucose (in mg/dL or mmol/L). For example, a correction factor of 50 means 1 unit will lower your glucose by 50 mg/dL.
3. Enter your Target Blood Glucose:
   This is your ideal target before meals, such as 100 mg/dL.
4. Input Current Meal Info:
   • Carbohydrate Intake: Amount of carbs in grams you plan to eat
   • Current Blood Glucose: Your current reading before the meal

How the Calculation Works

• Carb Dose = Total carbs / Insulin-to-carb ratio
• Correction Dose = (Current BG − Target BG) / Correction Factor
• Total Dose = Carb Dose + Correction Dose

Important Notes

• Results are rounded and shown immediately as you type.
• This tool is for educational support only and not a replacement for clinical advice.
• Always consult your healthcare provider before adjusting insulin doses.