Terms of Use

Last updated: 27 October 2026.

The service

SleepCycleCalc provides free online calculators and educational articles about sleep timing, based on the average 90-minute sleep cycle. By using the site you accept these terms.

Not medical advice

Nothing on this site is medical advice, a diagnosis, or a treatment plan. Sleep guidance ranges shown here are general information for healthy adults and children, drawn from widely published recommendations. Individual needs vary, and real sleep cycles vary (roughly 80–110 minutes). If you have persistent sleep problems, excessive daytime sleepiness, breathing disturbances in sleep, or any related health concern, consult a qualified medical professional. Do not delay seeking care because of something calculated here.

Accuracy

We work to keep calculations and content correct, but the service is provided "as is" without warranties of any kind. You are responsible for how you use the results.

Pro tier

A paid Pro tier is described on the pricing page as planned and "coming soon". It is not currently offered, no payment is collected, and its planned features or price may change or never launch.

Acceptable use

Use the tools for personal, lawful purposes. Do not attempt to disrupt the service or misrepresent its outputs as professional or medical guidance to others.

Liability

To the maximum extent permitted by law, SleepCycleCalc and its operator are not liable for any loss arising from reliance on the calculators or content.

Changes

These terms may be updated; the current version will always be posted here. Questions via the contact page.