Sleep Calculator
Optimal Bedtime & Wake-up Time Based on Sleep Cycles
Calculate the best times to sleep or wake up based on 90-minute sleep cycles. Plan your sleep scientifically for refreshed mornings.
😴 What are Sleep Cycles?
A sleep cycle lasts approximately 90 minutes and includes 3 stages of NREM sleep and REM sleep. Waking up at the end of a cycle minimizes sleep inertia (grogginess). Completing 4-6 cycles (6-9 hours) per night is ideal for most adults.
(includes 15 min to fall asleep)
📊 Recommended Sleep by Age
| Age Group | Recommended | Acceptable Range |
|---|---|---|
| Newborn (0-3 mo) | 14-17 hours | 11-19 hours |
| Infant (4-11 mo) | 12-15 hours | 10-18 hours |
| Toddler (1-2 yr) | 11-14 hours | 9-16 hours |
| Preschool (3-5 yr) | 10-13 hours | 8-14 hours |
| School Age (6-13 yr) | 9-11 hours | 7-12 hours |
| Teen (14-17 yr) | 8-10 hours | 7-11 hours |
| Adult (18-64 yr) | 7-9 hours | 6-11 hours |
| Senior (65+ yr) | 7-8 hours | 5-9 hours |
📝 How to Use
- Choose a mode: Wake-up time or Bedtime
- "Wake-up mode": Set when you want to wake up to get ideal bedtimes
- "Bedtime mode": Set when you go to bed to get ideal wake-up times
- 15 minutes to fall asleep is automatically included
- Prioritize 5-6 cycle options (7.5-9 hours)
💡 Tips for Better Sleep
- Go to bed and wake up at the same time every day
- Avoid blue light (phone, PC) 1 hour before bed
- Keep bedroom temperature at 65-68F (18-20C)
- No caffeine within 6 hours of bedtime
- Limit naps to 20 minutes or less
❓ FAQ
Sleep follows a ~90-minute cycle from light sleep to deep sleep to REM sleep. Waking at the end of a cycle minimizes sleep inertia (that groggy feeling).
On average, a healthy adult takes about 10-20 minutes to fall asleep. 15 minutes is the commonly accepted average.
Trying to repay sleep debt all at once has limited benefits. A consistent sleep schedule is much healthier for your body and mind.
📚 Guía local de cálculo
Lógica de fórmula
Se aplican fórmulas públicas de finanzas, préstamos, ratios y conversión.
Alcance de fuentes
Tomamos como referencia estándares públicos y prácticas habituales por país.
Supuestos
Impuestos, comisiones, tasas y límites cambian según región e institución.
Result Interpretation
Usa este resultado como escenario base. Antes de decidir, compáralo con oferta real y fiscalidad local.
Configuración local
Moneda: EUR
Unidades: metric
Modelo fiscal: US payroll estimate
Aviso normativo
Esta herramienta usa valores locales para estimación. Las condiciones reales y límites legales dependen de la entidad y del país.
Acciones recomendadas
- Compara al menos 2-3 entidades locales antes de contratar.
- Verifica por escrito comisiones, impuestos y cláusulas de prepago.
- Simula un escenario de estrés con +1-2% de interés.
Antes de decidir, verifica las reglas actualizadas de la entidad local.