Insulin Sensitivity Factor Calculator

Use this free browser-based tool to calculate your Insulin Sensitivity Factor (ISF) instantly. The ISF tells you how much one unit of insulin will lower your blood glucose level. This tool uses the standard 1800 Rule (rapid-acting insulin) and 1500 Rule (regular insulin). No uploads, no servers — everything runs privately in your browser.

Total Daily Insulin (TDD)

Insulin Sensitivity Factor (ISF)

About Insulin Sensitivity Factor Calculator

The Insulin Sensitivity Factor (ISF) Calculator from SmallToolsOnline helps you estimate how much one unit of insulin will lower your blood glucose level. It is widely used for diabetes management planning.

What Does It Do?

How To Use It

  1. Enter your Total Daily Insulin Dose (TDD).
  2. Select insulin type (Rapid, Regular, or Custom).
  3. Click Calculate ISF.
  4. View your result instantly in the output box.

This tool is for educational purposes and should not replace medical advice from a healthcare professional.

Free Usage and Premium Limits

This tool is free for personal use with up to 10 calculations per day per tool.

Upgrade to Premium for unlimited usage and full access to all health and calculation tools.

Premium Benefits

Why Use This Tool?

Common Use Cases

Final Thoughts

This calculator is designed to make insulin sensitivity estimation simple and accessible. Always consult a healthcare provider for medical decisions.

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