The HOMA Index (most commonly reported as HOMA-IR) is a practical way to estimate insulin resistance using two fasting lab values: glucose and insulin. If you are tracking metabolic health, prediabetes risk, or response to lifestyle changes, this can be a useful trend marker over time.
What is HOMA-IR?
HOMA stands for Homeostatic Model Assessment. The HOMA-IR score estimates how hard your body is working to keep blood sugar in range. A higher score generally suggests lower insulin sensitivity (more insulin resistance).
Formula used in this calculator
If glucose is in mmol/L:
HOMA-IR = (Fasting Insulin × Fasting Glucose) ÷ 22.5
If glucose is in mg/dL:
HOMA-IR = (Fasting Insulin × Fasting Glucose) ÷ 405
How to use the calculator
- Enter your fasting glucose value from a lab test.
- Select the correct glucose unit (mg/dL or mmol/L).
- Enter fasting insulin in µU/mL.
- Click Calculate HOMA-IR to see your score and a general interpretation.
General interpretation guide
| HOMA-IR | General Interpretation |
|---|---|
| < 1.0 | High insulin sensitivity (often favorable) |
| 1.0 - 1.9 | Typical/acceptable in many healthy adults |
| 2.0 - 2.9 | Possible early insulin resistance |
| ≥ 3.0 | More significant insulin resistance likely |
Important: Cutoffs can vary by population, age, lab methods, and clinical context. Use this as an educational tool, not a diagnosis.
Why your score can change
HOMA-IR is sensitive to short-term and long-term factors. Changes over weeks to months are often more useful than one isolated value.
Common influences
- Body weight and waist circumference
- Sleep quality and sleep duration
- Physical activity and muscle mass
- Diet quality, meal timing, and carbohydrate load
- Stress hormones, illness, and some medications
Best practices when measuring HOMA-IR
- Get labs after an 8-12 hour fast.
- Try to keep test conditions similar each time (sleep, timing, hydration).
- Track trend data rather than reacting to a single reading.
- Review results with your clinician, especially if you have diabetes, PCOS, fatty liver, or cardiovascular risk factors.
Example calculation
If fasting glucose is 100 mg/dL and fasting insulin is 10 µU/mL:
HOMA-IR = (100 × 10) ÷ 405 = 2.47
This would typically fall in a range suggestive of possible early insulin resistance, depending on your individual context.
Bottom line
This HOMA index calculator provides a fast way to estimate insulin resistance from routine fasting labs. It is most powerful when used consistently over time alongside other markers such as A1C, fasting triglycerides, HDL, blood pressure, and waist measurement.