Wake window calculator
The chart behind the calculator
The ranges come from the consensus across major wake-window charts — see the full wake windows by age guide for the complete table, how to use the ranges, and the honest note on where these numbers come from (they're sleep-consultant convention, not medical guidance).
What the calculator can't know
It knows the chart; it doesn't know your baby. A short nap shrinks the next window. A big morning stretches it. Growth spurts, teeth, and daycare days bend everything. That's the actual reason we built HAL: it estimates the next nap from your baby's own recent rhythm, not a static chart — and it lives in the family group chat, so whoever is holding the baby sees it.
The calculator that updates itself
Text "woke 2:40" in your family thread and HAL answers "when's her next nap?" from her actual pattern — no app, nothing to install.
Meet HAL →Sources
- Cleveland Clinic — Wake Windows by Age (pediatrician-reviewed)
- American Academy of Sleep Medicine — Recommended Amount of Sleep for Pediatric Populations
- Dr. Craig Canapari, Yale Pediatric Sleep Center — Do Wake Windows Help Kids Nap Better?
HAL is a household coordination and logging assistant, not a medical service. Sleep needs vary from baby to baby; the ranges here are common patterns, not prescriptions. Wake-window and nap-count ranges in particular are sleep-practitioner conventions rather than formal medical guidance — medical bodies publish only total-sleep recommendations. For health concerns, contact your pediatrician or another qualified professional.