Epworth Sleepiness Scale (ESS) Calculator
Rate how likely you are to doze off in each of the eight everyday situations below. For each one, choose the option that best reflects your usual behaviour in recent times, even if you have not done the activity lately. Add up the points and you have your Epworth Sleepiness Scale score, a widely used clinical measure of daytime sleepiness. A score of 10 or below is considered normal; 11 or higher suggests excessive daytime sleepiness worth discussing with a doctor.
Formula
Worked example
A person rates: Q1=1, Q2=2, Q3=1, Q4=2, Q5=3, Q6=0, Q7=1, Q8=1. Total = 1+2+1+2+3+0+1+1 = 11. A score of 11 falls in the "Mild Excessive Sleepiness" band (11-12) and warrants a conversation with a doctor.
What is the Epworth Sleepiness Scale?
The Epworth Sleepiness Scale (ESS) is a brief, self-administered questionnaire developed by Dr. Murray Johns at the Epworth Hospital in Melbourne, Australia in 1991. It asks you to rate your usual chance of dozing off in eight common everyday situations on a 0-to-3 scale. The eight scores are summed to give a total between 0 and 24. Unlike a one-off subjective question such as "how sleepy do you feel?", the ESS captures habitual daytime sleepiness across multiple situations, which makes it more consistent and clinically informative. It is now one of the most widely used screening tools in sleep medicine worldwide, endorsed by many sleep societies and used in clinical trials for obstructive sleep apnea, narcolepsy, idiopathic hypersomnia, and restless legs syndrome.
How to complete the questionnaire accurately
For each of the eight situations, choose the number (0-3) that best reflects your usual behaviour in recent times. Use these anchors: 0 = would never doze, 1 = slight chance of dozing, 2 = moderate chance of dozing, 3 = high chance of dozing. Answer based on your typical behaviour even if you have not been in that situation recently. For example, if you never sit in a car as a passenger, estimate how likely you would be to doze. Complete all eight items before looking at the total. Research by the scale's author shows that discussing the expected results before completion can bias responses upward, so answer each question independently. The questionnaire takes fewer than 2 minutes to complete.
Understanding your score
Scores of 0-10 are generally regarded as normal, though the range 6-10 is "higher normal" and may warrant attention if accompanied by other symptoms. Scores of 11 and above are clinically significant and suggest excessive daytime sleepiness (EDS). Mild EDS (11-12) is often addressable with improved sleep hygiene. Moderate EDS (13-15) warrants a medical consultation to screen for treatable conditions such as obstructive sleep apnea. Severe EDS (16-24) requires prompt evaluation because it is associated with higher accident rates, impaired cognitive performance, and lower quality of life. People with narcolepsy, untreated sleep apnea, or idiopathic hypersomnia typically score 16 or above. Note that the ESS measures sleepiness, not sleep quality; someone who sleeps poorly but fights off daytime drowsiness may score low, while a short sleeper who readily naps may score high.
What conditions does the ESS help detect?
The ESS does not diagnose any condition on its own, but elevated scores prompt further investigation. Obstructive sleep apnea (OSA) is the most common cause of a high ESS score in adults; CPAP therapy typically reduces the score by 4-6 points in people with moderate-to-severe OSA. Narcolepsy, a neurological disorder causing uncontrollable sleep attacks, is associated with very high ESS scores (often 17 or above). Idiopathic hypersomnia, shift-work sleep disorder, circadian rhythm disorders, and restless legs syndrome (which fragments sleep) can all elevate the score. Non-sleep causes such as depression, hypothyroidism, certain medications (antihistamines, opioids, benzodiazepines), and chronic sleep restriction from lifestyle factors can raise the score independently of any formal sleep disorder. Always share the result with a clinician who can take a full history.
Epworth Sleepiness Scale score categories
| ESS Score | Category | Clinical Significance |
|---|---|---|
| 0-5 | Lower Normal Sleepiness | Typical; no action needed |
| 6-10 | Higher Normal Sleepiness | Still normal; monitor if increasing |
| 11-12 | Mild Excessive Sleepiness | Consider lifestyle and sleep hygiene review |
| 13-15 | Moderate Excessive Sleepiness | Consult a doctor; possible sleep disorder |
| 16-24 | Severe Excessive Sleepiness | Prompt medical evaluation recommended |
Five-band interpretation used in clinical sleep medicine. A score of 11 or higher is generally considered clinically significant.
Frequently asked questions
What is a normal ESS score?
A total score of 0-10 is considered within the normal range. Scores of 0-5 are "lower normal" and indicate very low daytime sleepiness. Scores of 6-10 are "higher normal" and still within accepted limits for most healthy adults. A score of 11 or higher is generally considered abnormal and suggests excessive daytime sleepiness that may need clinical investigation.
How is the ESS score calculated?
You rate eight everyday situations from 0 (would never doze) to 3 (high chance of dozing). Adding all eight ratings gives the total ESS score, which ranges from 0 to 24. The calculation is a simple sum with no weighting; every situation contributes equally.
Does a high score mean I have sleep apnea?
Not necessarily. A high ESS score indicates excessive daytime sleepiness, which is a symptom rather than a diagnosis. Sleep apnea is a common cause, but narcolepsy, idiopathic hypersomnia, depression, medications, chronic sleep debt, and other conditions can also produce high scores. A diagnosis of sleep apnea requires a formal sleep study (polysomnography or a home sleep apnea test).
Can I use this to monitor the effect of CPAP or other treatment?
Yes. The ESS is commonly used in clinical practice to track treatment response. Effective CPAP therapy for obstructive sleep apnea typically reduces the score by 4-6 points. Many sleep clinics ask patients to complete the ESS before treatment and again at follow-up appointments to measure improvement. Keep your historical scores so your clinician can see the trend.
Is the ESS the same as the Pittsburgh Sleep Quality Index (PSQI)?
No. The ESS measures excessive daytime sleepiness, while the Pittsburgh Sleep Quality Index (PSQI) measures overall sleep quality over the past month, covering aspects such as sleep duration, sleep disturbances, and sleep efficiency. The two tools are complementary: a clinician might use the ESS to screen for daytime symptoms and the PSQI to assess the quality of night-time sleep.
Is the ESS validated for children?
The standard adult ESS is validated for adults. For children and adolescents, a modified version called the ESS-CHAD (Children and Adolescents) exists with age-appropriate language. The adult version is generally used for teenagers 18 and older, but younger children should use the paediatric-adapted version under clinician guidance.