Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Sleep Cycle Calculator

Find your ideal bedtime by working backward from your wake-up time in complete 90-minute sleep cycles. Waking at the end of a cycle (rather than mid-cycle) leaves you feeling more refreshed than the same total hours timed less carefully.

Desired Wake Time (hours (24h format))

Number of Sleep Cycles (cycles)

Fill in the required fields to see your result.

Sleep

Optimal Nap Timing Calculator

Find your ideal nap window based on when you wake up and when you go to bed. Useful for avoiding grogginess and not disrupting your night sleep.

Morning Wake Up Time (hours (24h format))

Night Bedtime (hours (24h format))

Fill in the required fields to see your result.

Key differences

	Sleep Cycle Calculator	Optimal Nap Timing Calculator
Category	Sleep	Sleep
Inputs required	2	2
Result	Optimal Bedtime (hours)	Optimal Nap Start Time (hours)
What it does	Find your ideal bedtime by working backward from your wake-up time in complete 90-minute sleep cycles. Waking at the end of a cycle (rather than mid-cycle) leaves you feeling more refreshed than the same total hours timed less carefully.	Find your ideal nap window based on when you wake up and when you go to bed. Useful for avoiding grogginess and not disrupting your night sleep.