Sleep Cycle Calculator

Wake up refreshed by timing your sleep to complete 90-minute cycles. Enter your wake time to get ideal bedtimes, or your bedtime to get ideal wake times. Free sleep cycle calculator.

How to use the Sleep Cycle Calculator

  1. 1

    Choose whether you're setting a wake time or a bedtime.

  2. 2

    Enter the time (or tap 'Sleep now').

  3. 3

    See recommended times aligned to full 90-minute cycles.

  4. 4

    Aim for the recommended (5–6 cycle) option.

Frequently asked questions

Why 90-minute cycles?

A full sleep cycle is roughly 90 minutes; waking at the end of a cycle (rather than mid-cycle) tends to feel less groggy.

Why add 14 minutes?

That's the average time it takes an adult to fall asleep, so bedtimes account for it.

How many cycles should I aim for?

Most adults do best with 5–6 cycles (about 7.5–9 hours).

Tips & discussion

Share a trick, ask a question, or help others get more out of this tool.

Log in to share a tip or ask a question.

Loading tips…