Napping at 1:30 pm: how long, and when you'll wake up
Updated October 3, 2026 · Sources: NASA 1995 · Brooks & Lack 2006 · Tassi & Muzet 2000 · NINDS
Short answer
2:05 pm
alarm for a 20-minute nap starting at 1:30 pm (15 min to fall asleep + 20 min asleep). Full cycle: wake at 3:15 pm.
General information from population studies (NIH, CDC, NSF, AASM). It is not medical advice and does not replace a clinician who knows you.
Lie down at 1:30 pm and the clock runs like this: asleep by about 1:45 pm, up at 2:05 pm after twenty minutes, or 3:15 pm after one complete cycle.
If bedtime is 10:45 pm, there are 8 h 40 min between the end of a short nap at 1:30 pm and lights out. Early afternoon is the window the research favours — it matches the natural dip in alertness and sits far enough from bedtime.
Sleep inertia ratings from Brooks & Lack 2006, Tassi & Muzet 2000, Rosekind 1995 · as of October 3, 2026
Which length to pick at 1:30 pm
Early afternoon is the best-studied nap window: alertness naturally dips after lunch and you are still eight-plus hours from bed. Ten to twenty-six minutes gives the quickest return; a full 90-minute cycle is fine here if you need it.
Every nap length from 1:30 pm
| Nap | Alarm | Reaches | Grogginess | Set aside |
|---|---|---|---|---|
| 10 min | 1:55 pm | light sleep (N1-N2) | minimal | 25 min |
| 20 min | 2:05 pm | light sleep (N2) | low | 35 min |
| 26 min | 2:11 pm | light sleep, occasionally early deep sleep | low to moderate | 41 min |
| 30 min | 2:15 pm | often enters deep sleep (N3) | moderate | 45 min |
| 45 min | 2:30 pm | deep sleep (N3) likely | moderate to high | 60 min |
| 60 min | 2:45 pm | deep sleep (N3) | high | 75 min |
| 90 min | 3:15 pm | complete cycle including REM | low (waking near the end of a cycle) | 105 min |
15 minutes added for sleep onset · sources above · as of October 3, 2026
Sources
- A brief afternoon nap following nocturnal sleep restriction: which nap duration is most recuperative? — Sleep 29(6):831-840, 2006 (Brooks A., Lack L.)
- Alertness Management: Strategic Naps in Operational Settings — NASA Technical Memorandum 108839 (Rosekind M.R. et al.), 1995; also J Sleep Res 4(S2):62-66
- Sleep inertia — Sleep Medicine Reviews 4(4):341-353, 2000 (Tassi P., Muzet A.)
- Brain Basics: Understanding Sleep — NINDS (NIH)
General information from population studies (NIH, CDC, NSF, AASM). It is not medical advice and does not replace a clinician who knows you.