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Calculateur d'Heure de Coucher.

Calculez l'heure ideale de coucher selon votre heure de reveil

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FAQ

What time should I go to bed if I wake up at 7 AM?

A common cycle-based target is around 9:45 PM or 11:15 PM, depending on whether you aim for 6 or 5 cycles, with 15 minutes to fall asleep.

Why does bedtime matter for sleep quality?

Going to bed at a consistent time aligned with your wake-up target supports circadian rhythm and can reduce morning grogginess.

How to Use the Bedtime Calculator

Find the best times to fall asleep based on 90-minute sleep cycles and your wake-up time.

  1. Enter the time you need to wake up.
  2. See several recommended bedtimes.
  3. Pick one that gives you 5–6 complete cycles.

Sleep Cycle Logic

Bedtime

Bedtime = Wake time − (n × 90 min) − 15 min

Each cycle is ~90 minutes; allow ~15 minutes to fall asleep.

Example:

Input: wake 7:00, 5 cycles

Calculation: 7:00 − 450min − 15min

Result: ≈ 11:15 PM

Real-World Use Cases

Waking Refreshed

Wake at the end of a cycle, not mid-cycle.

Shift Work

Plan rest around irregular schedules.

Tips

Tips

  • Waking between cycles feels more refreshing than waking mid-cycle.
  • Adults generally need 5–6 cycles (7.5–9 hours).
Bedtime Calculator - What Time Should I Go to Bed? | Mathify