Nap Calculator
Choose your nap type below to see the exact wake-up time.
How This Works
Different nap lengths trigger different amounts of sleep depth. Short naps (10–20 minutes) stay in light sleep, so you wake up quickly without grogginess. Longer naps (60+ minutes) reach deep sleep, which is more restorative but can leave you groggy if you wake up mid-cycle. A 90-minute nap completes a full sleep cycle, which tends to produce the least grogginess of the longer options.
Formula
Example
Starting a nap at 2:00 PM: a 20-minute power nap ends at 2:20 PM, while a 90-minute full-cycle nap ends at 3:30 PM.
Frequently Asked Questions
What time should I wake up from a 20-minute power nap starting at 10:19 PM?
You'd wake up at 10:39 PM.
How long should a nap be?
20 minutes is ideal for a quick alertness boost without grogginess. 90 minutes completes a full sleep cycle for the least grogginess, but takes much longer.