Sleep calculator

Find the best time to go to bed or wake up so you finish complete 90-minute sleep cycles and wake up refreshed.

Free · No sign-up · Your files are processed on your device and never uploaded

How to use Sleep calculator

  1. Fill in a few fields…
    1

    Paste or type

    Put your content in the box - or try the example.

  2. Result appears instantly
    2

    Watch the result

    Pick the options you want - the defaults suit most files.

  3. TXTCopy the result
    3

    Download the result

    Ready in seconds. Your file never left your device.

Features

  • Answer updates as you type.
  • Clear breakdown you can copy.
  • Works on phone and desktop.

Free and private

The calculation runs in your browser. Nothing you type is sent or stored, and there is no limit.

Questions

How long is a sleep cycle?

About 90 minutes; 5-6 cycles is 7.5-9 hours.

Is it free?

Yes - free and unlimited, with no sign-up and no watermark.

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