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Babies need a lot of sleep — 14–17 hours a day as newborns and 12–16 hours from 4 to 12 months, including naps. Enter your child's age to see their total sleep need, the usual wake window (how long they can happily stay awake) and the number of naps.
Pick their morning wake-up time and the calculator suggests a bedtime that gives enough night sleep.
| Age | 4 months |
| Morning Wake-up Time | 07:00 |
| Total sleep in 24 hours | 12–16 h |
| Wake window (awake time between sleeps) | 1.5–2.5 h |
| Naps | 3–4 naps |
| Suggested bedtime for a 07:00 wake-up | 8:30 pm (≈ 10.5 h night sleep) |
12–16 h; 1.5–2.5 h; 8:30 pm (≈ 10.5 h night sleep).
Try this example →| Age | 18 months |
| Morning Wake-up Time | 06:30 |
| Total sleep in 24 hours | 11–14 h |
| Wake window (awake time between sleeps) | 5–6 h |
| Naps | 1 nap |
| Suggested bedtime for a 06:30 wake-up | 7:30 pm (≈ 11 h night sleep) |
1 nap; 7:30 pm (≈ 11 h night sleep).
Try this example →The time a baby can stay awake between sleeps before getting overtired — about 45–60 minutes for newborns and 2–3 hours at 6–7 months.
Usually between 13 and 18 months.
Between about 6:30 and 8:00 pm for most babies and toddlers, timed so they get 10–12 hours of night sleep.