Sleep Calculator

A sleep calculator determines the best times to sleep or wake up based on 90-minute sleep cycles. It helps you wake up during light sleep, feeling refreshed and alert.

Enter your age range and desired bedtime or wake-up time. The calculator uses 90-minute cycles and a 15-minute sleep latency to suggest optimal sleep times for maximum restfulness.

Select 'Go to bed at', choose your bedtime and age range, then click 'Calculate'. You’ll get recommended wake-up times that align with complete sleep cycles.

Choose 'Wake up at', input your wake-up time and age range, and click 'Calculate'. The calculator provides optimal bedtimes for 4, 5, or 6 sleep cycles.

Recommended sleep times vary by age to ensure complete cycles. Here’s a breakdown based on your calculator’s data:

Age Range	Ideal Bedtime (Example)	Ideal Wake-Up (Example)
0-3 months	7:00 PM - 9:00 PM	9:00 AM - 11:00 AM
4-11 months	7:30 PM - 9:30 PM	7:30 AM - 10:30 AM
1-2 years	8:00 PM - 9:30 PM	7:00 AM - 9:30 AM
3-5 years	8:00 PM - 9:00 PM	6:00 AM - 8:00 AM
6-13 years	8:30 PM - 9:30 PM	6:00 AM - 7:30 AM
14-17 years	9:00 PM - 10:00 PM	6:00 AM - 7:00 AM
18-45 years	10:00 PM - 11:00 PM	6:00 AM - 7:00 AM
46+ years	10:00 PM - 11:00 PM	6:00 AM - 7:00 AM

These are example times; the calculator adjusts based on your specific input.

Sleep duration varies by age to support health and development. Here are the recommendations from your calculator:

Age Range	Minimum Sleep (Hours)	Maximum Sleep (Hours)
0-3 months	14	17
4-11 months	12	15
1-2 years	11	14
3-5 years	10	13
6-13 years	9	11
14-17 years	8	10
18-45 years	7	9
46+ years	7	8

The calculator uses these ranges to suggest personalized sleep schedules.

Sleep cycles (about 90 minutes) include light sleep, deep sleep, and REM sleep. Waking at the end of a cycle reduces grogginess and boosts alertness.

Sleep latency is the time it takes to fall asleep, typically 15 minutes. The calculator accounts for this to ensure accurate timing for your sleep cycles.

Each sleep cycle includes: NREM 1 (light sleep), NREM 2 (deeper light sleep), NREM 3 (deep sleep for physical restoration), and REM (dreaming, for cognitive processing). Later cycles have more REM sleep.

This calculator is for overnight sleep. For naps, aim for a 20-minute power nap for alertness or a 90-minute cycle to include all sleep stages without grogginess.

The calculator uses 90-minute cycle and 15-minute latency averages from sleep research. While individual patterns vary, it offers a reliable guide for optimal sleep timing.