Nap Calculator
Find the ideal nap duration and wake time based on your goal: alertness boost, memory consolidation, or full cognitive recovery. Evidence-based nap timing. Free, instant.
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Disclaimer: Results are for informational purposes only and do not constitute medical advice, diagnosis, or treatment. Consult a qualified healthcare professional for personal guidance.
The Science of Strategic Napping
Napping is not simply a compensatory behaviour for the sleep-deprived. NASA research found that a 40-minute nap improved performance by 34% and alertness by 100% in their pilots. The key variables are nap length, timing relative to circadian rhythm, and the individual's nighttime sleep quality. The "post-lunch dip" — a genuine circadian trough in alertness occurring around 1–3pm — makes this window physiologically optimal regardless of whether the person ate lunch.
Three Evidence-Based Nap Types
Power nap (10–20 minutes): Stays in N1/N2 sleep, avoiding sleep inertia on waking. Best for quick alertness recovery. Slow-wave nap (60 minutes): Includes N3 deep sleep, enhancing declarative memory consolidation — useful before learning sessions. Full-cycle nap (90 minutes): Completes one cycle including REM, maximising cognitive restoration at the cost of longer time commitment.
FAQs
How long should a nap be?
10–20 min for alertness (no inertia). 60 min for memory. 90 min for full cycle recovery.
Best time to nap?
1–3pm (circadian dip). After 3pm risks disrupting nighttime sleep.
What is a coffee nap?
Drink coffee then nap 20 minutes. Caffeine kicks in as you wake, combining both benefits. Research shows better alertness than either alone.