Enter your fasting glucose and fasting insulin and the page returns HOMA-IR. Glucose can be entered in mg/dL or mmol/L; the conversion is handled in code and both units are shown back to you. Both figures are values you read off a laboratory report.
HOMA-IR comes from the model published by Matthews and colleagues in 1985: fasting insulin in µIU/mL multiplied by fasting glucose in mg/dL, divided by 405. If glucose is entered in mmol/L the divisor is 22.5, and since 22.5 multiplied by 18 is 405 the two forms return the same number. Correlation with the euglycaemic clamp is reported at Rs of about 0.88. The page prints which form it used (as of October 2026).
This page only computes the number; it does not decide whether you have insulin resistance. Published cut-offs disagree: below 1.0, above 1.9, 2.5, and 2.5 to 3.0 all appear in the literature, so the reading changes with the cut-off chosen. HOMA-IR is also criticized as a simplified feedback model that does not capture dynamic physiology. None of this is a diagnosis; interpreting laboratory values and deciding on treatment is for a clinician who sees your full results.
Frequently asked questions
Fasting insulin in µIU/mL multiplied by fasting glucose in mg/dL, divided by 405. If glucose is in mmol/L the divisor is 22.5. Because 22.5 multiplied by 18 equals 405, both forms give the same result.
There is no single one. Some sources treat below 1.0 as normal, others use above 1.9 for early resistance, and others use 2.5 or a band of 2.5 to 3.0. That disagreement is why this page reports the value without ruling on it.
This page accepts µIU/mL only. A conversion factor from pmol/L is not confirmed in an authoritative source, so ask the laboratory and enter the µIU/mL figure.