HOMA-IR Calculator
Enter your fasting glucose and fasting insulin levels to calculate your HOMA-IR score, a widely used clinical estimate of insulin resistance. You also get the QUICKI index, the HOMA-beta cell function estimate, a plain-English interpretation of your result, and a step-by-step breakdown of the math. Choose between mmol/L or mg/dL for glucose - the calculator converts automatically.
Formula
Worked example
Fasting glucose 90 mg/dL (5.00 mmol/L), fasting insulin 8 mU/L: HOMA-IR = (8 × 5.00) / 22.5 = 40 / 22.5 ≈ 1.78 (normal range). QUICKI = 1 / (log10(8) + log10(90)) = 1 / (0.903 + 1.954) = 1 / 2.857 ≈ 0.350 (borderline range). HOMA-beta = (20 × 8) / (5.00 - 3.5) = 160 / 1.5 ≈ 107%.
What is HOMA-IR?
HOMA-IR stands for Homeostatic Model Assessment for Insulin Resistance. It is a mathematical formula, published by Matthews et al. in 1985, that estimates how well your body responds to insulin using just two routine fasting lab values: your fasting blood glucose and your fasting serum insulin. A healthy pancreas releases just enough insulin to keep blood glucose steady after a fast. When cells become resistant to insulin, the pancreas must produce more to achieve the same effect, pushing the product of the two values up. HOMA-IR captures that relationship in a single number. It does not replace the gold-standard hyperinsulinemic-euglycemic clamp test, but it is far less invasive and is widely used in both clinical practice and research because it correlates well with the clamp and requires no special equipment beyond a standard blood draw.
How to use this calculator
You need two values from the same fasting blood sample, drawn after at least 8 hours without food or caloric drinks. Enter your fasting glucose in either mg/dL or mmol/L using the unit selector - the calculator converts automatically. Enter your fasting serum insulin in mU/L (the unit uIU/mL is numerically identical). The calculator returns your HOMA-IR score, the QUICKI index, and an estimated HOMA-beta cell function percentage. Use the step-by-step panel to see exactly how each number was computed with your values. The gauge shows where your HOMA-IR sits relative to commonly used thresholds, and the reference table below describes what each band means clinically.
QUICKI index and HOMA-beta explained
The QUICKI index (Quantitative Insulin Sensitivity Check Index) is an alternative sensitivity estimate: 1 divided by the sum of the base-10 logarithms of insulin and glucose in mg/dL. Higher QUICKI values mean better insulin sensitivity. A QUICKI above 0.45 is generally considered healthy, values between 0.30 and 0.45 suggest possible insulin resistance, and values below 0.30 may indicate diabetes risk. QUICKI uses a logarithmic scale so it is less skewed by very high values than the linear HOMA-IR, and some researchers find it marginally better at separating healthy from insulin-resistant individuals. HOMA-beta estimates pancreatic beta-cell function as a percentage: (20 x insulin) / (glucose in mmol/L - 3.5). A value near 100% approximates normal function in the original model. Lower values suggest declining beta-cell capacity, and very high values can appear in early insulin resistance when the pancreas compensates by secreting more insulin. Note that HOMA-beta is undefined when fasting glucose is at or below 3.5 mmol/L (63 mg/dL).
Why no single cut-off fits everyone
One of the most important caveats with HOMA-IR is that no universally accepted threshold exists. The same score can mean different things in different populations. U.S. adults in the NHANES dataset had a median HOMA-IR of about 2.2 and a mean of 2.8. Normal-weight U.S. adolescents averaged 2.3, while obese adolescents averaged 4.9. Studies in Asian populations consistently find that meaningful cardiometabolic risk begins at lower HOMA-IR values, typically around 1.4 to 2.0, because body-fat distribution and beta-cell response differ from populations used to derive the original thresholds. Many clinical studies use 2.0, 2.5, or 3.0 as their cut-off, so the interpretation you read depends on which paper your clinician is following. Always interpret your score alongside other metabolic markers and with advice from your doctor.
What conditions are linked to elevated HOMA-IR?
Insulin resistance, as reflected by a high HOMA-IR, is a central feature of several common conditions. Type 2 diabetes and pre-diabetes are the most directly linked: as cells resist insulin more, the pancreas eventually cannot compensate and blood glucose rises. Metabolic syndrome, a cluster of abdominal obesity, elevated triglycerides, low HDL cholesterol, high blood pressure, and impaired fasting glucose, is strongly associated with elevated HOMA-IR. Polycystic ovary syndrome (PCOS) features insulin resistance in a substantial proportion of affected people regardless of weight, and treatment that improves insulin sensitivity can improve menstrual regularity and fertility outcomes. Non-alcoholic fatty liver disease (NAFLD) is tightly linked to hepatic insulin resistance, and HOMA-IR correlates well with liver fat on biopsy. Cardiovascular disease risk is also elevated in people with persistently high HOMA-IR scores, independent of other traditional risk factors.
Improving insulin sensitivity
The evidence for lifestyle interventions is strong. A 5 to 10 percent reduction in body weight consistently lowers HOMA-IR in overweight and obese individuals. Exercise - particularly two to three sessions per week of high-intensity interval training or resistance training - improves insulin signalling in muscle cells within weeks. Dietary patterns matter too: Mediterranean and plant-based diets, which emphasise vegetables, legumes, whole grains, nuts, and olive oil while limiting refined carbohydrates and ultra-processed foods, are associated with lower insulin resistance in multiple large trials. Adequate sleep (seven to nine hours per night) and stress management reduce cortisol, which otherwise antagonises insulin action. Pharmacological options include metformin, GLP-1 receptor agonists, and dual GLP-1/GIP agonists such as tirzepatide, which can produce large reductions in HOMA-IR, particularly in people with obesity or type 2 diabetes.
HOMA-IR interpretation ranges
| HOMA-IR | Interpretation | Clinical action |
|---|---|---|
| Below 1.0 | Optimal insulin sensitivity | Maintain healthy lifestyle |
| 1.0 - 1.9 | Normal to borderline | Monitor, maintain healthy habits |
| 2.0 - 2.9 | Insulin resistance likely | Lifestyle review; discuss with clinician |
| 3.0 and above | Significant insulin resistance | Medical evaluation recommended |
Thresholds vary by population and study. No single universal cut-off exists. Values above reflect commonly cited clinical and research benchmarks.
Frequently asked questions
What is a normal HOMA-IR score?
There is no single universally accepted cut-off, and thresholds vary by population and study. In most North American and European research, a HOMA-IR below 2.0 is considered normal for non-diabetic adults. Some studies use 2.5 or 3.0 as the threshold for insulin resistance. Asian populations tend to develop metabolic complications at lower values, often around 1.4 to 2.0. Always interpret your result in the context of your other metabolic markers and with guidance from your clinician.
Do I need to fast before the blood test?
Yes, and fasting is important. Both glucose and insulin fluctuate substantially after eating, so any result from a non-fasting sample will likely overestimate your HOMA-IR and be uninterpretable. Standard practice is to fast for at least 8 hours and to avoid caloric drinks (coffee with milk, juice, etc.) during that window. Plain water is fine.
My insulin is reported in pmol/L - how do I convert it?
Divide the pmol/L value by 6.945 to convert to mU/L (equivalently uIU/mL). For example, 55 pmol/L divided by 6.945 equals approximately 7.9 mU/L. Some labs report insulin in pmol/L, particularly in the UK and Canada. Check the units on your lab report before entering the value here.
What is the difference between HOMA-IR and QUICKI?
Both estimate insulin sensitivity from fasting glucose and insulin, but they use different mathematics. HOMA-IR is the product of the two values divided by a constant, so it scales linearly with glucose and insulin and tends to be skewed by very high values. QUICKI takes the reciprocal of the sum of their base-10 logarithms, which compresses extreme values and can make it slightly better at separating healthy from insulin-resistant individuals in some studies. In practice they are closely correlated and either can be used. Higher QUICKI values and lower HOMA-IR values both indicate better insulin sensitivity.
Can HOMA-IR diagnose diabetes?
No. HOMA-IR is a measure of insulin resistance, not a diagnostic test for diabetes. Diabetes is diagnosed by fasting glucose at or above 126 mg/dL (7.0 mmol/L), a 2-hour glucose of 200 mg/dL or above on an oral glucose tolerance test, a random glucose of 200 mg/dL or above with symptoms, or an HbA1c at or above 6.5%. A high HOMA-IR score should prompt further evaluation and lifestyle review, but it is a research and screening tool, not a diagnostic criterion.
Why is my HOMA-beta very high?
A very high HOMA-beta estimate often reflects compensatory hyperinsulinism in early insulin resistance. When cells become less sensitive to insulin, the pancreas responds by secreting more, which can drive HOMA-beta well above 100%. Over time, if insulin resistance persists, beta-cell function typically declines and HOMA-beta falls. A low HOMA-beta alongside a high HOMA-IR suggests significant beta-cell impairment and warrants prompt clinical evaluation.
Is HOMA-IR useful in people already taking medication for diabetes?
Its interpretation is more complex in treated individuals. Medications that lower blood glucose (such as metformin or insulin therapy) alter the glucose-insulin relationship in ways that make the HOMA-IR estimate less reliable. For people taking exogenous insulin, the formula is not applicable at all because injected insulin does not reflect endogenous secretion. If you are on diabetes medication, discuss with your clinician whether HOMA-IR is an appropriate monitoring tool for you.
Sources
- Matthews DR et al. Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia. 1985;28(7):412-419.
- Katz A et al. Quantitative insulin sensitivity check index: a simple, accurate method for assessing insulin sensitivity in humans. Journal of Clinical Endocrinology and Metabolism. 2000;85(7):2402-2410.