Free baby sleep tools
🛏️ Baby bedtime calculator
Bedtime works best a full wake window after the last nap ends, inside a healthy window for your baby’s age. Enter both and we will suggest tonight’s bedtime.
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Healthy bedtime window by age
| Age | Bedtime window | Last wake window |
|---|---|---|
| Newborn (0 to 6 weeks) | 17:00 to 21:00 | 30m to 1h 30m |
| 3 months | 18:00 to 20:00 | 1h to 1h 45m |
| 6 months | 18:00 to 20:00 | 2h to 3h |
| 9 months | 18:00 to 20:00 | 2h 45m to 3h 45m |
| 12 months | 18:00 to 20:00 | 3h 8m to 4h |
| 18 months | 18:30 to 20:00 | 5h to 6h |
| 24 months | 18:30 to 20:00 | 5h to 6h |
The last wake window matters most
The stretch between the last nap and bedtime is usually the longest of the day. If it is too short, babies can fight bedtime because they are not tired enough. Too long, and they can become overtired and wake more in the night.
Early bedtimes are allowed
After a day of short or missed naps, an earlier bedtime is one of the most reliable ways to help a baby catch up. Bringing bedtime forward by 20 to 30 minutes for a night or two is fine.
Let OBubba do this for you
This chart is the average baby. OBubba learns yours.
OBubba learns your baby’s own wake windows from what you log, predicts the next nap and bedtime, and spots over 30 common sleep disruptions with a gentle plan for each. Free to download.
Questions parents ask
Frequently asked questions
Is 7pm a good bedtime for a baby?
For most babies from about three months, yes. Anywhere between 6pm and 8pm tends to fit the natural evening rise in melatonin.
Why does my baby fight bedtime?
Common reasons are a last nap that ended too close to bedtime, too much day sleep, or being overtired from a long stretch awake. The calculator helps with the first two.
Can a baby go to bed too early?
It can happen when there is a lot of day sleep, and it sometimes shows up as a long awake spell in the night or a very early start. Very early bedtimes are best kept for catching up after a short-nap day.
Related guides
More free tools
Baby sleep schedule makerA full sample day of naps and bedtime from your baby’s age and wake-up time.
Wake window calculatorHow long your baby can comfortably stay awake between sleeps.
Why is my baby waking at night?Answer a few questions to see the most likely reasons for night wakes.
How much sleep does my baby need?How much sleep your baby needs in 24 hours, at night and in the day.
Sleep regression checkerWhich common sleep shake-ups line up with your baby’s age, and what helps.
Nap transition checkerIs your baby ready to drop a nap? Four signs to check.Sources
OBubba tools give general, age-based information. They are not medical advice and do not diagnose anything. Every baby is different. If you are worried about your baby, speak to your health visitor, midwife, GP or call NHS 111 (or your local equivalent).