Daily health

Sleep Calculator

Find sleep or wake times using 90-minute sleep cycles and a 15-minute fall-asleep estimate.

Your sleep times will appear here

Enter a wake or sleep time to see cycle-friendly options.

Tutorial

Sleep Calculator Tutorial

This tool suggests sleep or wake times based on 90-minute sleep cycles and a short fall-asleep estimate.

How to use

  1. Choose whether you want to wake up at a time or sleep at a time.
  2. Enter the target time.
  3. Click Calculate Sleep Times.
  4. Review the cycle-friendly options.

Example

If you want to wake up at 6:00 AM, the tool suggests bedtime options for 4, 5 or 6 sleep cycles.

Tips

  • Most sleep cycles are roughly 90 minutes, but people vary.
  • Use this for planning, not medical sleep advice.

Benefits

Makes bedtime planning easier.
Shows multiple sleep-cycle options.
Helps avoid guessing wake and sleep times manually.

Frequently asked questions

This tool suggests sleep or wake times based on 90-minute sleep cycles and a short fall-asleep estimate.

Yes. You can use this tool directly in the browser without creating an account.

Calculation history is not saved unless the site owner enables recent-calculation storage.