18:0000:0006:0012:00
7.5 h in bed · 6.5 h asleep · 87% efficiencyNot in the past monthLess than once a weekOnce or twice a week3+ times a week
What sleep quality is, in short
Sleep quality is more than how long you sleep. It combines how quickly you fall asleep, how much of your time in bed you spend asleep, how often you're disturbed, whether you rely on sleep aids, how rested you feel and how well you function the next day.
Those seven parts come from the Pittsburgh Sleep Quality Index (1989), the most widely used sleep questionnaire in research. This test follows its structure and scoring with our own wording, so the "above 5" line is a rough guide rather than a validated cut-off.
By What's Your IQ · Reviewed 4 Oct 2026- Format
- 4 sleep times, 10 frequency questions, 1 overall rating
- Score
- 7 components × 0–3 = 0–21; lower is better
- Guide line
- Above 5 suggests poor sleep quality
- Adults need
- 7–9 hours a night (18–64); 7–8 hours (65+)
SLEEP CYCLES
When should you go to bed?
Sleep runs in cycles of roughly 90 minutes. Waking at the end of one tends to feel easier than waking in the middle. Set your alarm time to see bedtimes that fit whole cycles, allowing 15 minutes to fall asleep.
6 CYCLES · 9 H21:45Ideal for most adults
5 CYCLES · 7.5 H23:15Recommended range
4 CYCLES · 6 H00:45Short night
3 CYCLES · 4.5 H02:15Emergency only
6 h × 14 nightsmatched two nights with no sleep at allIn a lab study, people limited to six hours a night for two weeks ended up as impaired on attention tests as people kept awake for two nights, yet they rated themselves only slightly sleepy.3
1989Seven components. Buysse and colleagues at Pittsburgh published the sleep quality index this test follows. A total above 5 separated good and poor sleepers with high accuracy.1
2003Sleep debt builds unnoticed. The six-hour study in the panel showed performance keeps falling with chronic short sleep while feelings of sleepiness level off.3
2015How much is enough. An expert panel for the US National Sleep Foundation recommended 7–9 hours for adults aged 18 to 64.2
2016Therapy before pills. The American College of Physicians recommended CBT for insomnia as the first treatment for chronic insomnia in adults.4
- Buysse, D. J., Reynolds, C. F., Monk, T. H., Berman, S. R., & Kupfer, D. J. (1989). The Pittsburgh Sleep Quality Index. Psychiatry Research, 28(2), 193–213.
- Hirshkowitz, M., et al. (2015). National Sleep Foundation's sleep time duration recommendations. Sleep Health, 1(1), 40–43.
- Van Dongen, H. P. A., Maislin, G., Mullington, J. M., & Dinges, D. F. (2003). The cumulative cost of additional wakefulness. Sleep, 26(2), 117–126.
- Qaseem, A., et al. (2016). Management of chronic insomnia disorder in adults. Annals of Internal Medicine, 165(2), 125–133.