About

SleepCalculator is a completely free, science-based sleep calculator designed to help you align your schedule with your body's natural 90-minute sleep cycles.

We built this tool because we believe everyone deserves a good night's sleep without having to pay for expensive apps or surrender their personal data. That's why SleepCalculator operates 100% locally in your web browser. Your sleep data, your bedtime inputs, and your age selections never leave your device.

Our calculations are strictly based on widely accepted sleep science, specifically the 90-minute restorative sleep cycle and the age-based sleep duration recommendations published by leading organizations like the American Academy of Sleep Medicine.

Made by GHC.
Contact: greyhat.cloud@gmail.com
This website is served securely via Cloudflare.