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.

Questions or suggestions? Get in touch. We read everything.