HOMA-IR Calculator

Calculate your HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) from fasting glucose and fasting insulin. The most widely used research index for estimating insulin resistance. Educational reference only.

Educational use only. HOMA-IR is a research screening index — not a diagnostic test. Reference ranges vary by population, lab assay, and age. Results require interpretation by a healthcare provider. Values must come from a standardized 8–12 hour fasting blood draw.

🔬 HOMA-IR Calculator

HOMA-IR Result

HOMA-IR score
Interpretation
HOMA-%B
β-cell function %
Fasting glucose
mg/dL
Fasting insulin
µIU/mL
Calculation:

HOMA-IR Reference Ranges

HOMA-IR ValueInterpretationClinical Context
< 1.0Optimal insulin sensitivityLow metabolic risk
1.0 – 1.9Normal rangeAcceptable in most adults
2.0 – 2.9BorderlineMonitor; consider lifestyle review
3.0 – 4.9Insulin resistance likelyDiscuss with provider; metabolic syndrome risk
≥ 5.0Significant insulin resistanceHigh risk; clinical evaluation warranted

Thresholds vary by study and population. Some references use ≥ 2.5 as the resistance threshold. Discuss your result in context with your provider.

HOMA-IR Formula

HOMA-IR = (Fasting Glucose mg/dL × Fasting Insulin µIU/mL) ÷ 405

Developed by Matthews et al. in 1985, HOMA-IR uses a mathematical model of the fasting glucose-insulin feedback loop. The denominator 405 converts units so the result is dimensionless (normal ≈ 1.0 in a healthy non-diabetic adult). The mmol/L version uses a divisor of 22.5 instead of 405.

What your HOMA-IR score is really telling you

HOMA-IR takes two numbers from a single fasting blood draw — your glucose and your insulin — and answers one practical question: how hard is your body working to keep blood sugar normal? When insulin is doing its job well, a modest amount holds glucose in range and your score stays low. When your cells start tuning insulin out, the pancreas compensates by releasing more of it. Your glucose can still look perfectly "normal" on a standard test, but that quietly elevated insulin is what pushes HOMA-IR up — which is why the score often spots a problem years before fasting glucose alone does.

That head start is the whole point. A slowly climbing HOMA-IR is frequently the first measurable hint of the drift toward prediabetes, type 2 diabetes, fatty liver, and the wider cluster of changes called metabolic syndrome. Treat it as a screening signal rather than a verdict, though — one value on one morning can't capture the full picture, and it only means something when you read it alongside your weight, blood pressure, lipids, and family history.

Why fasting properly changes your result

HOMA-IR is only valid on genuinely fasting blood. Anything with calories in the hours beforehand lifts both glucose and insulin, inflating the score and making it unreliable. The accepted standard is an 8–12 hour overnight fast with nothing but water, followed by an early-morning draw before you've eaten, exercised hard, or had coffee.

Common reasons a score reads higher than expected

A carb-heavy dinner the night before, a fast that was too short, a recent illness or poor night's sleep, acute stress, and some medications such as steroids can all nudge insulin upward temporarily. Insulin assays also differ between labs, so a small shift between tests may reflect the lab, not your body. If a result surprises you, the most useful next step is usually to repeat it under clean, consistent fasting conditions before drawing any conclusions.

Steps that can lower a high HOMA-IR over time

Insulin resistance responds to the same habits that improve metabolic health overall, and the changes don't have to be dramatic to register. Losing even 5–7% of body weight, walking after meals, building muscle through resistance training, easing back on refined carbohydrates and sugary drinks, and protecting your sleep all help your cells respond to insulin again. Improvements tend to show up over weeks to months rather than days, so retest under the same fasting conditions to compare fairly — and use the trend, with your provider's input, to guide what's working.

Frequently Asked Questions

A HOMA-IR under about 1.0 reflects optimal insulin sensitivity, and roughly 1.0–1.9 is normal for most healthy adults. Values of 2.0–2.9 are borderline, and 3.0 or above suggests insulin resistance. Cut-offs vary by population and lab, so interpret the result with your provider.

HOMA-IR = (fasting glucose in mg/dL × fasting insulin in µIU/mL) ÷ 405. If glucose is in mmol/L, divide by 22.5 instead. Both values must come from the same fasting blood sample.

A high HOMA-IR means your body is producing more insulin than normal to keep glucose in range — a sign of insulin resistance, which is linked to type 2 diabetes, metabolic syndrome, and PCOS. It is a screening signal, not a diagnosis.

Yes. HOMA-IR requires fasting glucose and fasting insulin, typically after 8–12 hours without food. Non-fasting values make the result invalid because eating raises both glucose and insulin.

Sources

  1. Matthews DR et al. "Homeostasis model assessment: insulin resistance and β-cell function." Diabetologia. 1985;28:412–419.
  2. Levy JC et al. "Correct homeostasis model assessment (HOMA) evaluation uses the computer program." Diabetes Care. 1998;21(12):2191–2192.

Last reviewed: June 2025

HOMA-IR is a research screening tool. Reference ranges vary by population and lab. Results require clinical interpretation. Educational use only.