HOMA-IR and HOMA-B calculator
Enter fasting glucose and fasting insulin from the same blood sample to get HOMA-IR, an estimate of insulin resistance, and HOMA-B, an estimate of beta-cell function. The numbers are for information; they are not a diagnosis of insulin resistance or diabetes.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Choose the unit of your glucose result: mg/dL or mmol/L.
- Enter fasting glucose and fasting insulin (µU/mL, also written mIU/L or mU/L) from the same morning sample.
- Read HOMA-IR and HOMA-B.
The original HOMA1 equations (Matthews et al., 1985):
- HOMA-IR = glucose (mmol/L) × insulin (µU/mL) ÷ 22.5 = glucose (mg/dL) × insulin ÷ 405
- HOMA-B (%) = 20 × insulin ÷ (glucose mmol/L − 3.5) = 360 × insulin ÷ (glucose mg/dL − 63)
Worked example
Fasting glucose 90 mg/dL and insulin 10 µU/mL: HOMA-IR = 90 × 10 ÷ 405 = 2.22; HOMA-B = 360 × 10 ÷ (90 − 63) = 3600 ÷ 27 = 133.3 %. The same sample in SI units is 5.0 mmol/L: 5 × 10 ÷ 22.5 = 2.22.
Tips
- Use glucose and insulin from the same sample; values from different days do not belong together.
- HOMA is not reliable for people who inject insulin, and insulin assays differ between labs, so compare results from the same lab.
- A single HOMA-IR value is a rough estimate. Doctors judge it together with weight, waist, blood pressure, lipids and HbA1c.
- This page is for information only and is not a diagnosis.
Frequently asked questions
What is a normal HOMA-IR?
There is no single agreed cut-off. Lower values mean better insulin sensitivity, and values around 1 are typical of insulin-sensitive adults, but the threshold for insulin resistance used in studies varies with the population and the insulin test, often somewhere between about 2 and 3. Ask the lab or your doctor which reference they use.
What does HOMA-B mean?
HOMA-B estimates how well the beta cells of the pancreas make insulin, as a percentage of a reference population. It cannot be calculated when fasting glucose is 3.5 mmol/L (63 mg/dL) or lower, because the formula divides by glucose minus that value; the calculator then leaves it out.
Why must the sample be fasting?
The model describes the steady state after an overnight fast, usually 8 to 12 hours without food. After a meal both glucose and insulin rise and the result means nothing.
My insulin is in pmol/L. What do I enter?
The calculator needs µU/mL (the same as mIU/L). Convert with the factor your lab gives, since labs and insulin assays differ, or ask the lab for the result in µU/mL.