Your workspace
Today’s plan
Keep what happened separate from what you are considering next. Update a record, compare again, and carry a clear snapshot forward.
Start with the last wake time, a sleep, or an unsuccessful attempt. You do not need a full day of records.
Record and compare your day
I don’t know which interval to use
An interval is the awake time from waking until the next sleep starts. It is different from nap length. You do not need to guess a number to use this page.
Leave with a useful record, even without a time estimate
- Record the last wake time you know. Mark other times as unknown if needed.
- Record whether a nap happened, was tried without sleep, or was not offered. Keep these different.
- Save what you have for yourself or another caregiver. Add the next actual sleep when it happens.
A missed nap by itself cannot choose a new bedtime. Keep following any existing care instructions; use the guide to review your situation rather than inventing an interval.
Add a known event first to enable saving your record.
Choose a situation
What happened today?
Choose a starting point. Nothing is recorded until you submit an entry.
Plan for later
Compare using the last recorded wake and your settings. Nothing is added to your actual record.
Start with what you know. You can save your record without comparing times. Record what happened
Save or share this dayRecorded
Recorded sleep: 0–0 minutes. This includes only the sleep you’ve recorded.
No actual events recorded yet.
Your day
Opening day…2026-10-11 · UTC · Age not entered · 0 recorded entries
Choose Save on this device to keep this day after closing the tab.
Dates, time zone and data options
Understand records, estimates and comparisons
What you explicitly entered as having happened.
A future assumption. Never added to recorded sleep.
A range of possible times. Unknown stays unknown.
Recorded — solid line
- No recorded entries yet.
Plan for later — dashed line
- Compare settings to see a possible plan. Nothing is selected automatically.
Sequence view, not a time scale. Estimated ranges and unknown times stay visible. Planned sleep is excluded from recorded totals.
Was this useful for your situation?
How this was worked out
We add your interval to the last recorded wake time. With ranges, the earliest wake plus the shortest interval gives the earliest result; the latest wake plus the longest interval gives the latest result. Later planned naps use your assumed duration, so uncertainty can widen.
Trying to settle without sleep and not offering a nap do not reset the wake time. Unknown times remain unknown. A plan never becomes a recorded event just because its time has passed.
These calculations do not determine when a baby will sleep, recommend a nap transition, or diagnose a sleep problem. No age-based rules are approved in this version. Follow any professional care plan and seek professional advice for health concerns or persistent difficulties.
Method and sources
Current method: user-defined interval arithmetic, version 1. No medical review is claimed. For general sleep and care information, see American Academy of Pediatrics: baby sleep. That resource is not used to derive an individual wake interval.