About BedtimeCalculation
BedtimeCalculation started with a simple observation: most people pick their bedtime by accident, whenever the show ends or the scrolling stops, and then wonder why a "full night's sleep" still leaves them exhausted.
The answer is usually timing. Sleep moves in roughly 90-minute cycles, and waking at the end of a cycle feels completely different from waking in the middle of one. Our sleep calculator does that math for you, and our companion tools help with the rest of the picture:
- Nap calculator: the right nap length for the boost you need
- Sleep needs by age: National Sleep Foundation recommendations
- Sleep debt tracker: see how much rest you owe your body
- Sleep apnea screener: the clinically validated STOP-BANG questionnaire
Our principles
- Free, forever. The site is supported by unobtrusive ads.
- Private by design. Your data (like sleep logs) stays in your browser; we have no accounts and no server-side storage.
- Evidence-based. Recommendations follow published sleep science and National Sleep Foundation guidance.
- Not medical advice. Our tools inform; they don't diagnose. Persistent sleep problems deserve a doctor's attention.
About our content & methodology
Our articles and calculators are produced by the BedtimeCalculation Editorial Team and built on published sleep science, drawing on guidance from the National Sleep Foundation, the NIH, the American Academy of Sleep Medicine, and the CDC. Every in-depth article cites its sources, and we review our cornerstone content regularly. For the full picture of how we research, write, and review, see our editorial standards & sources.
Questions or suggestions? Get in touch. We read everything.