STOP-BANG Score Calculator — Obstructive Sleep Apnea Risk

STOP-BANG is an eight-item questionnaire developed by Frances Chung and colleagues to screen adults for obstructive sleep apnea (OSA). The name is an acronym: each letter is one item, each item scores 1 (criterion met) or 0, and the total ranges from 0 to 8. This tool asks you the four symptom questions and computes the four measurement items for you, so you never have to self-judge “is my BMI over 35?”

• S — Snoring loudly (your answer).
• T — Tiredness / daytime sleepiness (your answer).
• O — Observed apnea, choking or gasping in sleep (your answer).
• P — high blood Pressure, diagnosed or treated (your answer).
• B — BMI > 35 kg/m² (derived from your height and weight).
• A — Age > 50 years (derived).
• N — Neck circumference > 40 cm (derived).
• G — Gender male (derived).

BMI is calculated with the standard formula BMI = weight kg ÷ (height m)². The cut-offs above are strict inequalities taken verbatim from the University Health Network reference at stopbang.ca — a BMI of exactly 35, an age of exactly 50, or a neck of exactly 40 cm each score 0, not 1.

The total maps to three risk bands from Chung et al. (Chest 2016): low risk 0–2, intermediate risk 3–4, and high risk 5–8. A higher score means a higher probability of moderate-to-severe OSA. Because the questionnaire is highly sensitive but less specific, a low score is good at ruling apnea out, while a high score flags who should have a sleep study rather than confirming a diagnosis.

There is also an enhanced high-risk rule for the intermediate band. A score of 3–4 is upgraded to high risk when two or more of the STOP symptoms are present and at least one of: the person is male, BMI is over 35 kg/m², or the neck is over 43 cm (men) / 41 cm (women). This raises specificity for moderate-to-severe OSA. The calculator applies it automatically and tells you when it fires. Every score is also cross-checked by a second, independent calculation so you can trust the number.

• Chung F, Abdullah HR, Liao P. STOP-Bang Questionnaire: A Practical Approach to Screen for OSA. Chest. 2016;149(3):631–638
• Chung F, et al. STOP questionnaire: a tool to screen patients for OSA. Anesthesiology. 2008;108(5):812–821
• University Health Network / Toronto Western Hospital — official STOP-BANG scoring reference (stopbang.ca)

The scoring, risk bands and enhanced high-risk criteria on this page were last cross-checked against these sources on 2026-07-16. The STOP-BANG cut-offs are stable, but the page is reviewed whenever the published guidance changes.