First ThingGuides › Tool
Bedtime calculator
Put in the time you need to be up and how much sleep you need. It counts back, with time to fall asleep, and gives you a bedtime.
Be in bed by
22:45
For 8 hours of sleep. For 7 hours: 23:45. For 9 hours: 21:45.
How much sleep do I need?
The NHS says most adults need between 7 and 9 hours. The right amount for you is the one that keeps you awake through the day without leaning on caffeine.
What about sleep cycles?
Many calculators count back in 90-minute cycles. Cycles vary between people and between nights, so treat 90 minutes as a rough guide. Enough sleep at a steady time matters more.
Let your alarm do this every night.
First Thing plans tonight's bedtime from tomorrow's alarm, eases it earlier before an early start, and reminds you to wind down.
