Quick answer: the World Health Organization defines burn-out in ICD-11 as a syndrome resulting from chronic workplace stress that has not been successfully managed, with three dimensions: exhaustion, mental distance or cynicism toward the job, and reduced professional efficacy. Crucially, the WHO classifies it as an occupational phenomenon, not a medical condition, and says the term should be used for the work context only.

"Burnout" is one of those words that has been stretched until it covers everything from a hard week to a psychiatric emergency. That is a problem, because the treatment for a hard week and the treatment for a psychiatric emergency are not the same, and neither is who provides it.

The ICD-11 entry, in plain terms

Burn-out appears in ICD-11 under code QD85. Three things about the entry matter more than the wording itself.

It is caused by work, chronically

The definition is causal: the syndrome results from chronic workplace stress that has not been successfully managed. Not from a bad month. Not from personal weakness. Something in the interaction between a person and their work has been unresolved for a long time. That framing puts a share of the problem outside the individual, and outside anything an app can fix.

It has three dimensions, and they are not synonyms

Dimension What it looks like How it is usually noticed
Energy depletion / exhaustionTiredness that rest does not clear; running on effort rather than capacity.First, by the person themselves.
Mental distance / cynicismFlatness, negativism, irritation about work that used to feel worth doing.Often first by colleagues or partners.
Reduced professional efficacyWork genuinely taking longer, quality slipping, small decisions becoming hard.Last, and often by the employer.

Because they do not arrive together, any single question — "are you tired?" — measures at most one third of the construct. It is also why the order of arrival is useful information in itself, covered in early warning signs of burnout.

It is a phenomenon, not a diagnosis

ICD-11 places burn-out in the chapter on factors influencing health status and contact with health services — the part of the classification used for reasons people come into contact with healthcare that are not themselves illnesses. The WHO states plainly that burn-out is not classified as a medical condition.

This has practical consequences. It means no doctor can hand you a burnout diagnosis in the way they can hand you one for depression or an anxiety disorder. It means your symptoms will be assessed for whatever is classifiable — which is why the depression question comes up so often, and why it deserves its own guide: burnout vs depression.

It applies to work only

ICD-11 is explicit that the term refers specifically to phenomena in the occupational context and should not be applied to describe experiences in other areas of life. "Parenting burnout" and "relationship burnout" are real experiences and reasonable phrases in ordinary speech, but they are outside this definition.

What the definition leaves out

ICD-11 describes burn-out; it does not give diagnostic criteria, thresholds or a validated instrument. There is no blood test and no official score. Research instruments exist — the Maslach Burnout Inventory being the best known — but a self-administered questionnaire on a Tuesday is not a clinical assessment.

So the honest position for any consumer tool, this one included, is narrow: you can measure conditions associated with chronic stress, and you can measure whether they are getting worse. You cannot measure burnout itself. Anything claiming otherwise is overselling.

Why it still matters that work is in the definition

If burnout is defined by unmanaged chronic workplace stress, then the workplace is not background — it is the mechanism. A systematic review with meta-analysis in BMC Public Health found that low workplace support and low job control are associated with burnout symptoms, and that job support is protective for emotional exhaustion.

Working hours sit in the same territory. WHO and ILO joint estimates associate working 55 hours or more per week with an estimated 35% higher risk of stroke and 17% higher risk of dying from ischaemic heart disease compared with 35–40 hours — a cardiovascular finding rather than a burnout one, but a useful marker of where load stops being survivable. See long working hours and your health.

The uncomfortable implication: individual habits are worth optimising, and they will not out-run a role with no autonomy and no support. Sleep hygiene is not a substitute for changing the job.

How to use the definition practically

Measure the conditions, honestly

Pulse tracks the signals associated with chronic stress against your own baseline, publishes its whole method in the app, and never claims to diagnose anything.