Health calculators

STOP BANG Calculator

Updated Sep 20, 2026 By Infinity Calculator
Rate Formulas Medical disclaimer

STOP — Symptom Criteria

Questions S, T, O and P. Each “Yes” scores 1 point.

S — Snoring. Do you snore loudly?

Loud enough to be heard through closed doors, or loud enough that your bed partner elbows you at night.

T — Tired. Do you often feel tired, fatigued or sleepy during the daytime?

Includes falling asleep while sitting quietly, reading or driving.

O — Observed. Has anyone observed you stop breathing, gasp or choke during your sleep?

Reported by a bed partner, family member or caregiver.

P — Pressure. Do you have, or are you being treated for, high blood pressure?

Answer Yes if you take any blood-pressure-lowering medication.

BANG — Demographic & Anthropometric Criteria

Questions B, A, N and G. Each “Yes” scores 1 point.

B — BMI. Is your BMI greater than 35 kg/m²?

A BMI over 35 kg/m² qualifies as Yes. Use the BMI calculator below if you are unsure of your BMI.

Inline BMI Calculator

Units

A BMI greater than 35 kg/m² scores as “Yes” for this question. The BMI calculator does not answer question B for you — select Yes or No above.

A — Age. Are you older than 50 years?

Answer Yes if your age is 51 years or above.

N — Neck. Is your neck circumference greater than 40 cm (16 inches)?

You can measure your neck circumference using a flexible measuring tape around the middle of your neck. Threshold: 40 cm = 16 in.

G — Gender. Are you male?

This question reflects statistically significant differences in obstructive sleep apnea prevalence between biological sexes.

Your STOP-BANG Results

Risk Classification
High Risk of OSA Score 4 of 8
LabelValue

Reference: Chung F et al. Anesthesiology 2008; 108: 812–821. Chung F et al. Br J Anaesth. 2012; 108: 768–775.

Answer Breakdown
ItemCriterionGroupAnswerPoints
Score Visualisation
Step-by-Step Solution

Introduction

The STOP-BANG Calculator is a quick screening tool that checks your risk for obstructive sleep apnea (OSA). Sleep apnea is a common sleep problem where your breathing stops and starts many times each night. It can leave you tired, raise your blood pressure, and hurt your heart over time. Many people have it and never know.

STOP-BANG stands for eight simple yes-or-no questions: Snoring, Tired, Observed breathing pauses, blood Pressure, BMI over 35, Age over 50, Neck size over 16 inches (40 cm), and Gender. Each "Yes" is worth 1 point, so your score can be 0 to 8.

Answer all eight questions and press the button. The tool adds up your score and shows if your risk is low (0 to 2), medium (3 to 4), or high (5 to 8). You also get a chart, a step-by-step breakdown, and a built-in BMI calculator for the BMI question.

This tool does not give you a diagnosis. Only a sleep study can confirm sleep apnea. If your score is medium or high, show your results to a doctor and ask about testing.

How to use our STOP-BANG Calculator

Answer eight simple Yes or No questions about your sleep, your health and your body. The calculator gives you a STOP-BANG score out of 8, your risk level for obstructive sleep apnea (OSA), a chart, and a step-by-step breakdown of the math.

S (Snoring): Pick Yes if you snore loudly. That means loud enough to hear through a closed door, or loud enough to wake your bed partner.

T (Tired): Pick Yes if you often feel tired, worn out or sleepy in the daytime, such as nodding off while sitting, reading or driving.

O (Observed): Pick Yes if someone has seen you stop breathing, gasp or choke while you sleep.

P (Pressure): Pick Yes if you have high blood pressure or take any medicine for it.

B (BMI): Pick Yes if your BMI is above 35 kg/m². If you do not know it, use the built-in BMI tool: choose metric or imperial units, type your height and weight, then press "Calculate BMI." The tool shows your BMI, but you still need to pick Yes or No yourself.

A (Age): Pick Yes if you are older than 50 years.

N (Neck): Measure around the middle of your neck with a tape. Pick Yes if it is more than 40 cm (16 inches).

G (Gender): Pick Yes if you are male.

Calculate Risk Score: Press this button once all eight questions are answered. Your score, risk level and charts will show below.

Reset / Clear All: Press this to erase every answer and start over.

What Is the STOP-BANG Questionnaire?

The STOP-BANG questionnaire is a short screening tool that checks your risk of obstructive sleep apnea (OSA). It asks 8 simple yes-or-no questions. Each "yes" is worth 1 point, so scores run from 0 to 8. Doctors, sleep clinics, and surgery teams use it because it is fast and catches most people who have moderate or severe sleep apnea.

What Is Sleep Apnea?

Obstructive sleep apnea happens when the soft tissue in your throat relaxes and blocks your airway while you sleep. Your breathing stops and starts many times each night. You may not wake up fully, but your sleep is broken and your blood oxygen drops. Over time this can raise your risk of high blood pressure, heart disease, stroke, type 2 diabetes, and car crashes from daytime sleepiness.

What the 8 Letters Mean

The name is made of two parts. STOP covers symptoms. BANG covers body and background facts.

  • S (Snoring): You snore loud enough to be heard through a closed door.
  • T (Tired): You feel tired, worn out, or sleepy during the day.
  • O (Observed): Someone has seen you stop breathing, gasp, or choke in your sleep.
  • P (Pressure): You have high blood pressure or take medicine for it.
  • B (BMI): Your body mass index is over 35 kg/m².
  • A (Age): You are over 50 years old.
  • N (Neck): Your neck measures more than 40 cm (16 inches) around.
  • G (Gender): You are male.

What Your Score Means

  • 0 to 2 points: Low risk of sleep apnea.
  • 3 to 4 points: Middle (intermediate) risk.
  • 5 to 8 points: High risk of moderate to severe sleep apnea.

There is also a shortcut rule. If you answer "yes" to 2 or more STOP questions and you are male, have a BMI over 35, or have a large neck, your risk counts as high even if your total is only 3 or 4.

What to Do Next

A high score does not mean you have sleep apnea. It means you should get checked. Only a sleep study, done at home or in a lab, can give a real diagnosis. Take your score to your doctor and talk about testing. If you do have OSA, treatments like CPAP, an oral device, weight loss, or side sleeping can help you breathe and sleep better.

This tool is for information only. It does not replace advice from a doctor.

Formulas used

STOP sub-score
\text{STOP} = S + T + O + P
BANG sub-score
\text{BANG} = B + A + N + G
Total STOP-BANG score
\text{Total} = \text{STOP} + \text{BANG} = \sum_{i=1}^{8} x_i, \quad x_i \in \{0,1\}
Risk band from total score
\text{Risk} = \begin{cases} \text{Low} & 0 \le \text{Total} \le 2 \\ \text{Intermediate} & 3 \le \text{Total} \le 4 \\ \text{High} & 5 \le \text{Total} \le 8 \end{cases}
Composite high-risk override
\text{High Risk} \iff \text{STOP} \ge 2 \;\text{and}\; (B = 1 \;\text{or}\; N = 1 \;\text{or}\; G = 1)
Body mass index (metric)
\text{BMI} = \frac{\text{weight}_{\mathrm{kg}}}{\left(\frac{\text{height}_{\mathrm{cm}}}{100}\right)^2}
Body mass index (imperial, via unit conversion)
\text{BMI} = \frac{\text{lb} \times 0.45359237}{\left[(12\,\text{ft} + \text{in}) \times 0.0254\right]^2}
Gauge percentage of maximum score
\text{Gauge \%} = \frac{\text{Total}}{8} \times 100

Frequently asked questions

Is a STOP-BANG score of 3 bad?

A 3 is in the middle risk range, not the high range. But it is the point where doctors start paying attention.

A 3 becomes high risk if 2 or more of your "yes" answers come from the STOP part (snoring, tired, observed pauses, blood pressure) and you are male, have a BMI over 35, or have a neck over 40 cm. If that fits you, ask your doctor about a sleep study.

Can you have sleep apnea with a low STOP-BANG score?

Yes. A score of 0 to 2 means low risk, not zero risk.

Mild sleep apnea, and apnea in thin people or women, can be missed. If you still wake up gasping, have morning headaches, or feel wiped out every day, tell your doctor anyway. Symptoms matter more than the number.

Why does STOP-BANG use a BMI of 35 instead of 30?

The cut-off was set high on purpose so the question points to people with a much stronger link to blocked airways.

Extra fat around the neck and throat presses on the airway during sleep. A BMI over 35 makes that far more likely. People with a BMI of 30 to 35 can still have sleep apnea, but they usually pick up points from the other questions instead.

How do you measure neck circumference for sleep apnea?

Use a soft tape measure, the kind used for sewing.

  • Stand up straight and look forward.
  • Wrap the tape around the middle of your neck, just below the Adam's apple.
  • Keep the tape level and snug, not tight.
  • Breathe out and read the number.

More than 40 cm (16 inches) scores a point. Measure over bare skin, not a collar.

Why do hospitals ask STOP-BANG questions before surgery?

Because sleep apnea makes anesthesia riskier. People with OSA are more likely to have breathing trouble, low oxygen, or heart problems after an operation.

If your score is high, the surgery team may watch your oxygen more closely, use less sedation, or ask you to bring your CPAP machine. That is why the questionnaire was first created for surgery clinics.

Does STOP-BANG work for women?

Yes, but it is less sensitive in women because being male is worth a point.

Women often have quieter symptoms too, like tiredness, insomnia, or mood changes instead of loud snoring. A woman with a score of 3 should still be taken seriously. Some clinics use a lower cut-off for women.

What is the difference between STOP-BANG and the Epworth Sleepiness Scale?

They measure different things.

  • STOP-BANG screens for the risk of having sleep apnea using symptoms and body facts.
  • Epworth measures how sleepy you are during the day by asking how likely you are to doze off in 8 everyday situations.

You can be very sleepy with no apnea, or have bad apnea and feel fine. Doctors often use both together.

What happens during a sleep study?

There are two kinds.

  • Home test: You wear a small belt, a finger clip, and a nose tube in your own bed for a night or two. It tracks breathing and oxygen.
  • Lab test (polysomnography): You sleep overnight at a clinic with sensors on your head, face, chest and legs. It tracks brain waves and sleep stages too.

Both count how many times your breathing stops each hour. That number is called the AHI.

What AHI counts as mild, moderate, or severe sleep apnea?

AHI means apnea-hypopnea index, the number of breathing pauses per hour of sleep.

  • Under 5: normal
  • 5 to 15: mild
  • 15 to 30: moderate
  • Over 30: severe

STOP-BANG is built to catch moderate and severe cases, so an AHI above 15.

Can losing weight cure sleep apnea?

It can help a lot, and sometimes it clears up mild cases.

Losing about 10% of your body weight can cut your AHI by roughly 25%. It shrinks fat around the neck and belly so your airway stays open. But weight loss does not fix everyone, especially if jaw or throat shape is the cause. Keep using your CPAP until a repeat sleep study says otherwise.

Does sleeping on your side help sleep apnea?

Often, yes. Lying on your back lets your tongue and soft palate fall backward and block the airway.

Many people have far fewer pauses on their side. Some even have "positional" apnea that only happens on the back. Side sleeping is a free thing to try, but it is not a full treatment for moderate or severe OSA.

Why does age over 50 raise sleep apnea risk?

Throat muscles lose tone as you get older, so the airway collapses more easily during sleep. Body fat also shifts toward the neck and belly with age.

Sleep apnea becomes much more common after 50, and risk in women rises sharply after menopause when protective hormones drop.

Can children take the STOP-BANG questionnaire?

No. It was built and tested for adults only.

Kids with sleep apnea usually have large tonsils or adenoids, and their signs look different: restless sleep, bedwetting, mouth breathing, or acting hyper instead of sleepy. Children need a pediatric sleep check, not this score.

What is the difference between obstructive and central sleep apnea?

Obstructive apnea is a blockage. Your brain tells you to breathe, but your throat is closed, so you strain and gasp. This is the common type.

Central apnea is a signal problem. Your brain briefly stops telling you to breathe, so there is no effort at all. It is linked to heart failure, stroke, and some pain medicines. STOP-BANG only screens for the obstructive type.

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