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Sleep

Time your sleep around natural 90-minute cycles to wake up feeling rested, and understand what 'sleep debt' really means.

Sleep science research from the American Academy of Sleep Medicine and the NHS recommends 7–9 hours per night for most adults. Our sleep tools help you back-calculate the right bedtime and visualise how missed sleep accumulates across the week.

Calculators in this category

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Sleep Calculator

Find the best times to fall asleep or wake up by aligning with 90-minute sleep cycles.

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Bedtime Calculator

Pick a wake time and we'll work backwards through 90-minute cycles to suggest bedtimes.

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Guides in this category

sleep · 6 min read

How Much Sleep Do Adults Need?

Sleep guidelines from the AASM and NHS, plus how to tell if you're getting enough.

sleep · 7 min read

Sleep Debt Explained: Can You Catch Up On Lost Sleep?

What sleep debt is, how it accumulates, and the limits of weekend recovery.

Frequently asked: sleep