Epworth Sleepiness Scale Calculator (ESS Daytime Sleepiness Test)

The Epworth Sleepiness Scale (ESS) is an eight-item questionnaire published by Dr Murray Johns in 1991 to measure a person's general level of daytime sleepiness — their average propensity to doze off across a range of everyday situations, rather than how tired they feel at one moment.

1. Rate every situation 0–3. 0 = would never doze, 1 = slight chance of dozing, 2 = moderate chance, 3 = high chance of dozing. Answer for your usual way of life in recent times; if you have not done something lately, estimate how it would affect you.
2. Add the eight ratings. The total runs from 0 to 24. Every item carries equal weight — the score is a simple, unweighted sum with no age or sex adjustment, which is why the worked examples below reconcile exactly by hand.
3. Map the total to a severity band (Official Epworth Sleepiness Scale granular banding):
   • 0–5: Lower normal daytime sleepiness
   • 6–10: Higher normal daytime sleepiness
   • 11–12: Mild excessive daytime sleepiness
   • 13–15: Moderate excessive daytime sleepiness
   • 16–24: Severe excessive daytime sleepiness
4. Apply the clinical threshold. A total above 10 (that is, 11 or more) is the single most-cited cut-point for excessive daytime sleepiness (Johns 1991/1992). The five-band split simply refines the messaging above and below that line — it does not change the arithmetic.

The eight situations were chosen and validated because they differ in how strongly they provoke sleep: lying down to rest is highly soporific, while sitting and talking to someone rarely is. That spread lets the total distinguish ordinary tiredness from genuinely excessive sleepiness. A high ESS is a common symptom of untreated sleep disorders such as obstructive sleep apnoea, narcolepsy, and chronic sleep deprivation — but the scale flags how sleepy you are, not why. Only a clinician can find the cause.

Scoring is verified two ways in code: the band-table lookup is cross-checked against an independent cut-point derivation for every possible total from 0 to 24, so the number you see is reproducible to the point. Nothing you enter is uploaded — the calculation happens entirely in your browser.

• Johns MW — A new method for measuring daytime sleepiness: the Epworth sleepiness scale (Sleep, 1991)
• The Official Epworth Sleepiness Scale (MW Johns) — item wording and severity banding
• Johns MW — Reliability and factor analysis of the Epworth Sleepiness Scale (Sleep, 1992)

The eight items, the 0–3 response anchors, the 0–24 total, the severity bands, and the >10 threshold on this page were last cross-checked against the sources above on 2026-07-18. The ESS is © MW Johns and reproduced here for personal, non-commercial screening use.