Sleep Forecast How Plumi's Sleep Forecast works
With Plumi Pro, Sleep Forecast estimates the next nap and bedtime as windows, with about 15 minutes on either side. It starts with age guidance, then incorporates recent sleep logs once there are enough.
What Sleep Forecast shows
Your next nap window and bedtime appear as ranges, so you have time to wind down without watching for one exact minute. For babies under 8 weeks, Plumi skips the countdown and suggests following your baby's cues.
The Today card appears shortly before a window, during it, and for a short while afterward. It stays hidden while your baby sleeps, and you can hide it for today or turn it off. You can also choose a reminder 10 minutes before each nap or bedtime window, and see the next window on Apple Watch.
In the Sleep Plan, you can compare today's naps and bedtime in three columns: Actual (logged), Predicted, and Typical (age guidance). Up next shows awake time, naps today, and bedtime.
How a forecast is made
- 1 Start with age guidance Plumi uses the wake-window band and typical nap count for your baby's age, or corrected age for a baby born early.
- 2 Shape the day It uses shorter wake windows in the morning and longer ones before bed to estimate naps and bedtime.
- 3 Learn your baby's rhythm After at least 5 wake windows across 3 days of logged sleep, it blends age guidance with medians from your baby's last 7 days.
- 4 Keep the range useful It ignores gaps that look like a missed log and shows predictions as windows rather than exact times.
The age ranges Plumi uses
A wake window is the time your baby is awake between sleeps. Plumi uses the following age bands and nap counts as starting assumptions for its estimates. They are not a clinically validated schedule for an individual baby:
| Age | Wake window | Naps a day |
|---|---|---|
| 0–2 months | 45 min to 1 h 15 min | 5 |
| 3 months | 1 h 15 min to 1 h 45 min | 4 |
| 4–5 months | 1 h 30 min to 2 h 30 min | 3 |
| 6–7 months | 2 h to 3 h | 3 |
| 8–10 months | 2 h 30 min to 3 h 30 min | 2 |
| 11–13 months | 3 h to 4 h | 2 |
| 14–17 months | 4 h to 5 h | 1 |
| 18–36 months | 5 h to 6 h | 1 |
These windows stretch through the day: the morning window is shortest, and the one before bed is longest. They are starting points, not a schedule your baby has to meet. As Plumi learns from logged sleep, it adjusts toward your baby's recent pattern. Age guidance remains part of the estimate.
The total sleep bands below use AASM and NSF references, including naps. NSF gives the newborn range; AASM does not cover babies under 4 months. Plumi uses AASM’s 12–16 hours at 4–5 months and NSF’s 12–15 at 6–12 months. These are general reference bands, not individual sleep targets.
| Age | Total sleep in 24 hours |
|---|---|
| 0–3 months | 14–17 hours |
| 4–5 months | 12–16 hours |
| 6–12 months | 12–15 hours |
| 13 months–3 years | 11–14 hours |
| 3–5 years | 10–13 hours |
For babies born early, Plumi uses corrected age until age 2. You can see how these ranges look for any age with our free baby sleep calculator, or see a sample day with the nap schedule generator.
Logging a sleep after the fact
If your baby fell asleep before you opened Plumi, go to the Manual tab in the Sleep log and choose the real start time. Turn on Still sleeping, and a live timer will run from that time until you stop it. The same approach works with Still nursing, Still in the bath, and Still strolling.
Help the forecast use complete sleep logs
- Log when sleep actually started, even if you add it later.
- Stop an ongoing sleep when your baby wakes, so the log reflects the full sleep.
- Keep logging across days. Personalization begins after at least 5 wake windows across 3 days of logged sleep.
- Use the window alongside your baby's cues. For babies under 8 weeks, follow cues instead of a countdown.
Private by design
Sleep Forecast is computed on your device, from logs that stay on your device. If you turn on sync, your logs travel with end-to-end encryption, so our server can't read them.
Free and Pro
Sleep Forecast, the Sleep Plan, and Rhythm insights are part of Pro. If you use Plumi for free, you can open the Sleep Plan and Rhythm and explore them with an example baby. Tracking sleep itself stays free. See Plumi pricing.
What it can't do
A forecast can't tell you the exact moment your baby will fall asleep, and an unlogged sleep may leave it with an incomplete picture of the day. Sleep Forecast offers guidance, not medical advice. Talk to your pediatrician about medical concerns.
More on sleep: the sleep tracker · finding your baby's sleep rhythm
Sleep Forecast questions
When should my baby nap?
Sleep Forecast offers a next nap window based on age guidance and, once there are enough logs, your baby's recent sleep. Watch your baby's cues too, especially under 8 weeks, when Plumi does not show a countdown.
What is a wake window?
It's the time your baby is awake between sleeps. Plumi uses age-based wake windows as a starting point and lets them get longer through the day.
How long should a 6-month-old be awake between naps?
Plumi's age guidance for 6 to 7 months uses wake windows of 2 to 3 hours and 3 naps. Your baby's cues and logged pattern help put that guidance in context.
Does Sleep Forecast work for babies born early?
Yes. Plumi uses corrected age for babies born early until age 2.
How much sleep do I need to log before forecasts become personal?
Plumi begins blending in your baby's pattern after at least 5 wake windows across 3 days of logged sleep. It looks at medians from the last 7 days while keeping age guidance in the forecast.
Why can't I see the Today card right now?
The card appears 20 minutes before a window, during it, and for a short while after. It stays hidden while your baby sleeps, and you can also hide it for today or turn it off.
Can I try Sleep Forecast without Pro?
Yes. Free users can open the Sleep Plan and Rhythm insights and explore them with an example baby.
See an estimate for the next nap
Tracking is free forever. Plumi Pro adds Sleep Forecast, the Sleep Plan and Rhythm insights.
