Sleep Apnea Risk Calculator
Use the STOP-BANG questions below to estimate how strongly your symptoms and measurements suggest obstructive sleep apnea risk. The tool is designed for screening and awareness, not diagnosis.
Introduction
Obstructive sleep apnea happens when the upper airway repeatedly narrows or closes during sleep. Those pauses can lower oxygen levels, fragment sleep, and leave a person feeling unrefreshed even after spending enough time in bed. Common clues include loud snoring, choking or gasping awakenings, morning headaches, poor concentration, and excessive daytime sleepiness. The difficulty is that symptoms often build gradually, and many people do not notice nighttime breathing pauses unless a partner or family member points them out.
The STOP-BANG questionnaire is a practical way to turn those clues into a simple screening score. It combines four symptom questions with four body-measurement or demographic factors. Each item counts as either 0 or 1 point, so the total runs from 0 to 8. A low total suggests a lower screening risk, while a higher total suggests that formal sleep evaluation may be worthwhile. This calculator automates the count and also computes BMI from your height and weight so you can interpret the result more confidently.
How to Use
Start with the four checkbox questions. Check the box if the statement is true for you now or is regularly true according to a partner, family member, or clinician. Then enter your current weight in kilograms, height in centimeters, age in years, and neck circumference in centimeters. Finally, choose the sex option used for STOP-BANG scoring on this page and press Calculate Risk.
If you do not know one of the measurements, it is better to measure or look it up than to guess wildly. A neck circumference can be measured with a tape around the neck at a comfortable natural position. Height should be entered in centimeters rather than feet and inches, and weight should be entered in kilograms rather than pounds. Because the calculator uses the information exactly as entered, unit mix-ups can change the result dramatically.
- Answer the symptom questions honestly.
- Enter weight, height, age, and neck circumference in the units shown.
- Select the sex option used in this implementation of STOP-BANG.
- Read the BMI, total score, and risk band together rather than focusing on only one item.
The result area will show your calculated BMI, your STOP-BANG score out of 8, and the corresponding screening category. If you leave a number blank, the page treats that missing value as not adding a point. That keeps the calculator working, but it can make risk look lower than it really is, so complete entries are best whenever possible.
Formula
The questionnaire is additive. Every item that meets the scoring rule contributes one point, and every item that does not meet the rule contributes zero points. In shorthand, the total is the sum of the eight STOP-BANG components:
Here, S is loud snoring, T is daytime tiredness, O is observed breathing pauses, and P is high blood pressure or treatment for it. The remaining letters come from body or demographic factors: B for BMI, A for age, N for neck circumference, and G for the sex item. BMI itself is calculated from mass and height using the standard body mass index relationship:
In this implementation, the automated score adds one point when BMI is greater than 35 kg/m², age is greater than 50 years, neck circumference is greater than 40 cm, and the male option is selected. Those details matter because a threshold card right on the boundary, such as BMI 35.0 or age 50, does not add a point here unless the value goes above the cutoff. After the eight items are counted, scores of 0 to 2 are labeled Low risk, scores of 3 to 4 are labeled Intermediate risk, and scores of 5 to 8 are labeled High risk.
Example
Imagine a person who snores loudly, often feels tired in the daytime, and is being treated for high blood pressure. They weigh 110 kg, are 175 cm tall, are 54 years old, have a neck circumference of 42 cm, and select male for the final item. Their BMI is about 35.9, so the BMI item scores 1. Observed apnea is not known, so that item stays 0. The total is 1 for snoring, 1 for tiredness, 0 for observed apnea, 1 for pressure, 1 for BMI, 1 for age, 1 for neck circumference, and 1 for sex, giving a STOP-BANG score of 7 out of 8. That falls into the high-risk screening band and would be a strong reason to discuss a formal sleep evaluation with a clinician.
Limitations
STOP-BANG is a screening tool, not a diagnosis. It is useful because it is fast and sensitive, but it does not measure oxygen drops directly, does not record sleep stages, and does not confirm whether a person truly has obstructive sleep apnea on a sleep study. A low score can still occur in someone with meaningful symptoms, especially if they are younger, do not fit the typical body-size profile, or have a form of sleep-disordered breathing that the questionnaire does not capture well.
The score also does not account for everything that influences sleep apnea risk or severity. Alcohol use before bed, sedating medications, nasal obstruction, craniofacial anatomy, pregnancy, menopause, and certain neurologic or cardiopulmonary conditions can all matter. Central sleep apnea is a different disorder and may not be reflected by STOP-BANG at all. If you have dangerous sleepiness, near-miss driving episodes, witnessed long breathing pauses, or cardiovascular disease plus strong symptoms, seek professional care even if the screening score is not high.
About the STOP-BANG Sleep Apnea Assessment
Why clinicians use it
STOP-BANG is widely used because it is quick enough for clinics, preoperative assessments, dental screenings, and general health checkups, yet still captures many of the strongest predictors of obstructive sleep apnea. A person does not need special equipment to answer the questions, and the tool can highlight who should consider a home sleep apnea test or a full overnight study. Higher scores are associated with a greater chance of moderate to severe obstructive sleep apnea, but the main value of the questionnaire is triage: it helps decide who may need deeper evaluation sooner.
How the body-measurement items are handled on this page
To compute the B component of the STOP-BANG acronym, the calculator derives your Body Mass Index (BMI) from the weight and height fields. The BMI formula is expressed as:
where represents mass in kilograms and denotes height in meters. On this page, the score gains one point when BMI is greater than 35 kg/m², age is greater than 50 years, neck circumference is greater than 40 centimeters, and the male option is selected. Some published summaries describe these body thresholds with greater-than-or-equal wording, but this calculator follows the result logic exactly as implemented above, so boundary values at 35.0, 50, and 40.0 stay in the zero-point lane unless they are exceeded.
| Criterion | Yes = 1 | No = 0 |
|---|---|---|
| Snoring | + | |
| Tiredness | + | |
| Observed Apnea | + | |
| Pressure (Hypertension) | + | |
| BMI > 35 kg/m² | + | |
| Age > 50 years | + | |
| Neck > 40 cm | + | |
| Male sex item selected | + |
Interpreting the bands
Low risk does not mean no risk; it only means the questionnaire found fewer flagged items. Intermediate risk is a signal to look at symptoms and medical context more closely. High risk means the pattern of symptoms and measurements strongly supports further evaluation. People in the higher bands may benefit from discussing sleep testing, perioperative planning, blood pressure control, or treatment options such as CPAP, oral appliances, weight management, positional therapy, or other specialist-directed care.
Clinical context and next steps
Sleep apnea matters because untreated breathing interruptions can affect mood, attention, accident risk, blood pressure, heart rhythm, glucose control, and overall quality of life. Even mild-to-moderate disease can leave someone feeling chronically worn down. If your score is intermediate or high and you also have classic symptoms such as loud habitual snoring, witnessed apneas, or daytime sleepiness, it makes sense to share the result with a healthcare professional rather than treating it as an abstract number.
At the same time, the reverse is also true: a low screening result should not stop you from seeking care if symptoms are compelling. Clinical evaluation may include a sleep history, physical examination, and either an in-lab polysomnogram or a home sleep apnea test. Screening tools are best used as prompts for action and discussion. They work best when paired with symptom awareness, accurate measurements, and common-sense caution about drowsy driving or other safety-sensitive situations.
Mini-game: Airway Triage
This optional canvas game turns the questionnaire into a fast screening drill. Incoming clinic cards describe symptoms or measurements. Send each card left if it scores 1 STOP-BANG point, or right if it scores 0. The pace accelerates, and a few boundary-value cards test whether you remember the cutoffs used by this page.
The mini-game is separate from the calculator result and is here for practice and memorization only.