Sleep Calculator

Calculate suggested bedtimes using 90-minute sleep-cycle estimates.

Enter your values, then select the button.
Sleep Calculator method
Wake time - whole 90-minute cycles - sleep-onset time.

How to use the sleep calculator

  1. Desired wake time: Choose the time you want to wake up.
  2. Time to fall asleep (minutes): Estimated time between going to bed and sleep.
  3. Select the button and review the result.

Worked example

For a 7:00 wake time, options are shown for 4-6 estimated cycles.

Method and limitations

Wake time - whole 90-minute cycles - sleep-onset time.

Sleep cycles vary and timing alone cannot diagnose or treat sleep problems.

Common questions

Why might another result be different?

Inputs, rounding, policies, rates, and assumptions can differ. Compare like-for-like values and use current official information when a rate or rule can change.

Does NidXee save my entries?

No. The calculation runs in your browser. Reloading or closing the page may clear it.