Sources and Editorial References

Hirshkowitz M, Whiton K, Albert SM, et al.

National Sleep Foundation's sleep time duration recommendations: methodology and results summary.

Sleep Health. 2015;1(1):40–43.

This paper describes the methodology behind the National Sleep Foundation's age-based sleep duration recommendations and summarizes the expert panel's conclusions for each age group, from newborns through older adults. The recommended ranges for children (6–12: 9–12 hours), teenagers (13–17: 8–10 hours), adults (18–60: 7–9 hours), and seniors (65+: 7–8 hours) used in the Better Sleep Calculator's age group settings are informed by this source. The paper also highlights that "may be appropriate" ranges extend slightly beyond the recommended windows for individuals with distinct sleep needs.

Watson NF, Badr MS, Belenky G, et al.

Recommended amount of sleep for a healthy adult: a joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society.

Sleep. 2015;38(6):843–844.

A joint statement from two major sleep medicine organizations recommending that adults sleep 7 or more hours per night on a regular basis to promote optimal health and avoid health risks associated with habitual short sleep. This source informs the "7–9 hours" adult guidance used throughout the site and the framing that sleeping fewer than 7 hours per night is associated with adverse health outcomes. The site does not use this source to make specific health claims — only to contextualalize general sleep duration guidance.

Consensus Conference Panel.

Recommended amount of sleep for a healthy adult.

Journal of Clinical Sleep Medicine. 2015.

A companion document to the Watson et al. consensus statement, expanding on the reasoning and evidence behind the adult sleep duration recommendation. Used as a supporting source for the same adult sleep duration context. The site summarizes this guidance in plain language without reproducing text or overstating its conclusions.

Ohayon M, Wickwire EM, Hirshkowitz M, et al.

National Sleep Foundation's sleep quality recommendations: first report.

Sleep Health. 2017;3(1):6–19.

This paper covers the National Sleep Foundation's first attempt to formalize recommendations around sleep quality — not just quantity. It identifies dimensions of sleep quality including sleep continuity, feeling rested upon waking, and the absence of sleep-disturbing symptoms. The Better Sleep Calculator references this source in the Sleep Hygiene Guide to support the framing that behavioral and environmental factors meaningfully affect sleep quality, and in the Methodology to note that quality is outside the scope of what the calculator estimates.

Boivin DB, Boudreau P.

Impacts of shift work on sleep and circadian rhythms.

Pathologie Biologie. 2014;62(5):292–301.

A review of the mechanisms by which shift work disrupts sleep and circadian timing, including the challenges of sleeping during biologically "day" hours and the partial adaptation possible with permanent night schedules. This source informs the Shift Worker Sleep Guide content on circadian misalignment, light management, and the distinction between permanent and rotating shift schedules. The site summarizes this research in general language without making treatment claims.

Centers for Disease Control and Prevention (CDC).

Sleep and Sleep Disorders.

cdc.gov/sleep. Accessed 2026.

The CDC's public health pages on sleep provide general population-level context on sleep health, including prevalence of insufficient sleep and its public health implications. Used as supporting context in the Sleep Hygiene Guide. All claims are presented as general public health context, not medical recommendations. The site is not affiliated with the CDC.