HOMA-IR calculator (insulin resistance)
HOMA-IR = fasting glucose (mg/dL) × fasting insulin (µIU/mL) ÷ 405, or glucose in mmol/L × insulin ÷ 22.5. For example, a fasting glucose of 90 mg/dL and insulin of 10 µIU/mL gives a HOMA-IR of 2.22. There is no universal cut-off: published thresholds for insulin resistance range from about 1.8 to 3.5, depending on the population studied.
Last reviewed:
HOMA-IR calculator
The HOMA-IR formula
HOMA-IR = fasting glucose (mmol/L) × fasting insulin (µIU/mL) ÷ 22.5
HOMA-IR = fasting glucose (mg/dL) × fasting insulin (µIU/mL) ÷ 405
HOMA (homeostasis model assessment) was described by Matthews and colleagues in 1985. It uses the fact that fasting glucose and insulin settle into a balance set by how well insulin works and how much insulin the pancreas makes. The formula above is the simple approximation of that model, which is used far more widely than the full computer model. 405 is 22.5 Ă— 18, the mg/dL version of the same constant. We round HOMA-IR to two decimals and compare that rounded value with the cut-offs.
Published HOMA-IR cut-offs
There is no single, universally accepted HOMA-IR cut-off. Each study below derived its own threshold from its own population, which is why they range from 1.775 to 3.46.
| HOMA-IR | Population | How it was set | Study |
|---|---|---|---|
| 1.775 | Iranian adults without diabetes (national survey, n = 3,071) | Best cut-off for identifying metabolic syndrome | Esteghamati et al., 2010 |
| 1.85 | Spanish men without diabetes (EPIRCE study) | Cut-off for identifying metabolic syndrome | Gayoso-Diz et al., 2013 |
| 2.05 | Spanish general adult population (EPIRCE study, n = 2,459) | Cut-off for identifying metabolic syndrome | Gayoso-Diz et al., 2013 |
| 2.6 | Spanish adults with normal glucose metabolism (n = 65) | 75th percentile of the study group | Ascaso et al., 2003 |
| 3.46 | Spanish general adult population (EPIRCE study, n = 2,459) | 90th percentile of the population | Gayoso-Diz et al., 2013 |
What your result means
- Below 1.78: below every cut-off in the table, so not classed as insulin resistance by any of these studies.
- 1.78 to 3.46: above some cut-offs and below others. Whether this counts as insulin resistance depends on the population and definition used.
- 3.46 or above: above every cut-off in the table, which points to insulin resistance.
HOMA-IR is best at comparing groups; for one person a single test is imprecise, and it should be read alongside your fasting glucose, A1C and overall health. Insulin resistance is linked to a higher risk of type 2 diabetes and cardiovascular disease, and it often improves with weight loss and exercise, so a high result is a reason to talk to your doctor, not a diagnosis.
Frequently asked questions
What is a normal HOMA-IR?
There isn't one agreed normal value. Published cut-offs for insulin resistance vary with the population and method: for example 1.78 in Iranian adults and 2.05 in Spanish adults (both judged against metabolic syndrome), and 3.46 as the 90th percentile of the same Spanish population. Lower values mean the body needs less insulin to keep fasting glucose steady.
What does a high HOMA-IR mean?
A higher HOMA-IR means more insulin is needed to keep your fasting glucose steady, a sign of insulin resistance. Insulin resistance is associated with a higher risk of type 2 diabetes and cardiovascular disease. One result is an estimate, not a diagnosis, so talk to your doctor about it.
Do I need to fast for a HOMA-IR test?
Yes. HOMA-IR is defined for fasting (basal) glucose and insulin, both measured in the same fasting blood sample. Values taken after eating will give a misleading result.
My lab reports insulin in pmol/L. How do I convert it?
Ask your lab which conversion factor it uses. Two different factors are in common use for converting insulin between pmol/L and µIU/mL, and they differ by about 15%, which changes HOMA-IR by the same amount. This calculator expects insulin in µIU/mL, which is the same number as mU/L.
How accurate is HOMA-IR?
It works well across groups of people but is imprecise for one person. In the original 1985 study it correlated closely with the gold-standard clamp test (Rs = 0.88), but a single estimate had a coefficient of variation of about 31%, so a repeat test can differ noticeably from the first.
Is HOMA-IR the same as the TyG index?
No. Both estimate insulin resistance, but the TyG index uses fasting triglycerides and glucose instead of insulin, so it can be worked out from a routine blood test. Use our TyG index calculator to compare.
Sources
- Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC. Homeostasis model assessment: insulin resistance and β-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia. 1985;28(7):412–419.
- Wallace TM, Levy JC, Matthews DR. Use and abuse of HOMA modeling. Diabetes Care. 2004;27(6):1487–1495.
- Esteghamati A, Ashraf H, Khalilzadeh O, et al. Optimal cut-off of homeostasis model assessment of insulin resistance (HOMA-IR) for the diagnosis of metabolic syndrome: third national surveillance of risk factors of non-communicable diseases in Iran (SuRFNCD-2007). Nutr Metab (Lond). 2010;7:26.
- Gayoso-Diz P, Otero-González A, Rodriguez-Alvarez MX, et al. Insulin resistance (HOMA-IR) cut-off values and the metabolic syndrome in a general adult population: effect of gender and age: EPIRCE cross-sectional study. BMC Endocr Disord. 2013;13:47.
- Ascaso JF, Pardo S, Real JT, Lorente RI, Priego A, Carmena R. Diagnosing insulin resistance by simple quantitative methods in subjects with normal glucose metabolism. Diabetes Care. 2003;26(12):3320–3325.
- Knopp JL, Holder-Pearson L, Chase JG. Insulin units and conversion factors: a story of truth, boots, and faster half-truths. J Diabetes Sci Technol. 2019;13(3):597–600.
- McLaughlin T, Abbasi F, Cheal K, Chu J, Lamendola C, Reaven G. Use of metabolic markers to identify overweight individuals who are insulin resistant. Ann Intern Med. 2003;139(10):802–809.