Nap Calculator

Power nap, full cycle, or recovery · based on sleep cycle science

When are you starting your nap?

Your nap options

Best nap window: early-to-mid afternoon (roughly 1-3pm) works best for most people — it matches a natural energy dip and is early enough to avoid disrupting nighttime sleep.

How it works

  1. Enter when you're starting your nap (defaults to right now).
  2. We calculate 3 wake-up times based on sleep cycle research: a 20-minute power nap, a 60-minute recovery nap, and a 90-minute full-cycle nap.
  3. We add about 5 minutes to account for the time it typically takes to fall asleep.
  4. Pick based on your time available and goal — the 20-minute and 90-minute options are generally the least likely to leave you groggy.

Sleep cycle timing varies by individual. These are general guidelines based on typical sleep architecture, not a personalized sleep study.

Frequently asked questions

A 20-minute power nap is ideal for a quick energy boost without grogginess. A 90-minute nap completes a full sleep cycle including REM sleep, so you wake up at a natural point. Naps between 30-60 minutes often cause grogginess because they end during deep sleep.
Grogginess after napping (sleep inertia) usually happens when you wake up during deep, slow-wave sleep, which typically kicks in around 30-60 minutes into a nap. Waking up earlier or later tends to feel more refreshing.
Early-to-mid afternoon, roughly 1-3pm, tends to work best for most people — it aligns with a natural dip in alertness and is early enough to avoid interfering with nighttime sleep.
We add about 5 minutes to each nap length to account for the time it typically takes to actually fall asleep, so the wake-up times shown reflect a more realistic total time.

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