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Sleep Better Timer

Nap planning

Nap calculator

Nap timing is a planning estimate, not a guarantee that you will wake refreshed.

Time to fall asleep

How it works

Nap calculator

The nap calculator starts with your local nap start time, adds your selected fall-asleep estimate, then adds 10, 20, 30, or 90 minutes asleep. With a 10-minute fall-asleep estimate, a 1:00 PM start creates 1:20, 1:30, 1:40, and 2:40 PM options.

The 10-, 20-, 30- and 90-minute values are planning options, not prescribed nap lengths. Ninety minutes is a longer-nap estimate, not a promised full cycle. NIOSH sources here discuss nurses and work-related fatigue; that context does not establish a universal recommendation for every adult. CDC/NIOSH: Napping guidance

The arithmetic follows the same transparent limits described in the methodology.

Timing caution

Late naps may affect bedtime

A nap can be useful for planning a short rest, but daytime sleep can make bedtime harder for some people, especially later in the day. MedlinePlus: Healthy sleep

Use the late-day note as a caution, not a rule. Sleep needs, schedules, work, and stress vary by person.

If it is too late for a nap, try a short wind-down routine instead.

Nap calculator FAQ

How long should I nap?

The 10-, 20-, 30- and 90-minute values are planning options, not prescribed nap lengths. Ninety minutes is a longer-nap estimate, not a promised full cycle. NIOSH sources here discuss nurses and work-related fatigue; that context does not establish a universal recommendation for every adult.

Should I nap late in the day?

Late naps can make bedtime harder for some people. If it is already afternoon or evening, consider a shorter nap or an evening routine instead.

Can a nap replace a full night of sleep?

No. This page is for planning a short rest window. It does not diagnose sleep problems or replace enough regular nighttime sleep.

Sources

Sources and context

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