How Many Hours of Sleep Do You Actually Need? A Guide by Age

"Eight hours a night" is the number most people have heard, but sleep needs genuinely change across life stages, and the real evidence-based picture is a range rather than one fixed target.

Why it's a range, not a single number

Sleep researchers generally express recommendations as a range for each age group, not a single figure, because individual variation is real — some adults function well and consistently feel rested on the lower end of their range, while others genuinely need the upper end.

The general ranges for adults

For most adults (18–64), the commonly cited range is 7–9 hours per night. For older adults (65+), it shifts slightly lower, to around 7–8 hours, partly reflecting normal age-related changes in sleep architecture rather than older adults simply "needing less sleep" in a way that's fine to ignore.

Signs you're not getting enough — regardless of the "right" number

Daytime sleepiness, difficulty concentrating, irritability, and relying on caffeine to function are more useful personal indicators than chasing an exact hour count. If you consistently need an alarm to wake up and still feel groggy, that's a more meaningful signal than whether you hit a specific number.

Why sleep needs can shift with health and medicines

Illness, stress, pregnancy, and certain medicines can genuinely increase how much sleep your body needs, at least temporarily. Conditions covered in our guide on common causes of insomnia can also reduce how much restorative sleep you're actually getting even if you're spending enough time in bed.

When short sleep becomes a medical concern

Consistently getting well under the recommended range, especially alongside loud snoring, gasping, or pauses in breathing, is worth assessing rather than just accepting — see our guide on snoring vs sleep apnea for when that specific pattern needs a proper sleep study.

Where a sleep aid fits in

Medicines like zopiclone and other options in our sleep aids category are generally intended for short-term use while an underlying cause of poor sleep is identified and addressed — not as a way to permanently substitute for addressing genuine sleep debt or an unrecognised sleep disorder.

This article is general information, not medical advice. If you're consistently not getting enough sleep or feel unrefreshed despite enough time in bed, speak with a doctor to identify what's actually driving it.