Tools

HOMA-IR calculator

HOMA-IR is an index calculated from your fasting glucose and fasting insulin, used to estimate how readily your tissues respond to insulin. It is not a separate blood test and it is not a diagnosis — it is a screening number that a clinician reads alongside your symptoms and your other results.

Fasting glucose

Fasting insulin

Your HOMA-IR

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Enter both values to see your index.

How it is calculated

With glucose in mg/dL: HOMA-IR = (glucose × insulin) ÷ 405
With glucose in mmol/L: HOMA-IR = (glucose × insulin) ÷ 22.5

Insulin is in µU/mL (the same number as mIU/L). If your lab reports insulin in pmol/L, this calculator converts it for you.

What the number means — and what it doesn't

This is where most calculators overpromise. There is no internationally agreed HOMA-IR cutoff. Studies in different populations have used thresholds roughly between 2.0 and 3.0, and the right line differs by ancestry, age, body composition and — importantly — by which insulin assay your laboratory runs. Two labs can turn the same blood into different numbers.

So treat your result as a conversation starter, not a verdict. A higher index suggests your body may be producing more insulin to keep glucose normal; it does not by itself mean you have a condition, and a low index does not rule one out. HOMA-IR also performs poorly in people already taking insulin, and it is not used to diagnose diabetes — fasting glucose, HbA1c and an oral glucose tolerance test do that.

What to do with the result

Bring the actual numbers to your doctor — fasting glucose, fasting insulin and the lab's reference ranges, not just the index.
Ask about HbA1c if you have not had it. It reflects roughly three months of blood sugar and is a standard part of the picture.
Check the test was truly fasting — 8–12 hours, water only. A snack beforehand makes the number meaningless.
Do not start supplements on the strength of an index. Nothing sold for "insulin support" has been shown to change outcomes.

What does have strong evidence is unglamorous: in the Diabetes Prevention Program, a large randomised trial in adults with prediabetes, structured lifestyle change — around 7% weight loss plus about 150 minutes of activity a week — cut progression to type 2 diabetes by 58%, outperforming metformin in the same trial.

When to see a doctor sooner

Some symptoms should not wait for a routine appointment: intense thirst with frequent urination, unexplained weight loss, blurred vision, or fatigue that is new and severe. These can indicate blood sugar that is already high and need prompt medical assessment.

Frequently asked questions

What is a normal HOMA-IR?

There is no single normal value. Different populations and different laboratory insulin assays shift the range, and published studies have used thresholds roughly between 2.0 and 3.0. Your result should be read by a clinician alongside your reference ranges and symptoms.

Is HOMA-IR a blood test?

No. It is a calculation from two blood tests — fasting glucose and fasting insulin. You cannot order HOMA-IR on its own; you order those two and the index is derived.

Can HOMA-IR diagnose insulin resistance?

No. It estimates it. Diagnosis is a clinical judgement that takes in your history, examination and other results. HOMA-IR is a screening and research tool.

Does the test have to be fasting?

Yes — normally 8 to 12 hours, water only. Both values must come from the same fasting sample, otherwise the index means nothing.